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Full text of "A series of anatomical plates : with references and physiological comments, illustrating the structure of the different parts of the human body"

ENCYCLOPEDIA OF CHEMISTRY. 



NOW READY, 
NO. 1, PRICE 25 CENTS, 

OF 



THE ENCYCLOPEDIA OF CHEMISTKY, 

THEORETICAL AND PRACTICAL; 

PRESENTING A COMPLETE AND EXTENDED VIEW OF THE PRESENT STATE OF 

v CHEMICAL SCIENCE, 

WITH ITS NUMEROUS AND IMPORTANT APPLICATIONS TO 

MEDICAL SCIENCE, AGRICULTURE, THE ARTS AND MANUFACTURES. 

BASED UPON THE PLAN OF THE 

DICTIONARY OF CHEMISTRY, BY DR. URE, AND THE DICTIONARY OF THEORETICAL AND PRACTICAL CHEMISTRY, 

NOW PUBLISHING BY LIEBIG, POGGENDORF, WOHLER, &c. 

BY JAMES C. BOOTH, 

Member of the Am. Philosophical Society, and of the Academy of Nat. Sciences, Professor of Technical Chemistry in the Franklin Institute, 

and of Elementary Chemistry in the Philada. High School. 

The facility for easy reference offered by the Dictionary (rendering that form preferable to any other for works on Science and the Arts) has induced the author to adopt 
it in the publication of an 

ENCYCLOPEDIA OF PRACTICAL AND THEORETICAL CHEMISTRY, 

which, while it will embrace all the latest discoveries in the pure science of chemistry, shall at the same time exhibit the manifold applications of chemical principles ami 
theories to every department of the useful arts. 

The rapid advancement of chemical science in the path of discovery within a few years, has created a demand for treatises upon this subject which has not been fully 
answered by the several elementary works lately issued from the English press. 

While these works must be mentioned with unqualified praise as text books for the student of chemistry, it must at the same time be acknowledged that since they offer 
little more than an outline of the science, they cannot satisfy the thirst for more extended treatises, which may be employed as valuable works of reference by the advanced 
scholar, while their practical tendency shall enable the uninitiated to enter actively into the vast field of research. 

The wonderful developments in the 

CHEMISTRY OF ORGANIZED BEINGS AND ORGANIC MATTER 

during the la6t few years, now renders it imperative on the physician and student of medicine to be thoroughly conversant with these discoveries, whether with the view of 
understanding the great principles of life in a state of healtk or disease, or of administering with greater accuracy and precision the remedies required to sustain nature or 
restore a more healthy action. If we glance at the state of medical science previous to the rise of chemistry, we are forcibly struck with the crude and incongruous mixtures 
designed to sustain the delicate assemblage of organized materials in the human frame, and the no less absurd ideas respecting the sources of vital energy. 

The researches of chemical philosophers are gradually removing the veil involving these subjects in mystery, until, within a short space of time, the province of organic 
chemistry received an astonishing impetus, which is still cau-ying it forward, and will not cease until the many and varied operations of animal life shall be brought within 
the sphere of pure chemical action, of fixed and definite laws. 

Time has been when the processes of the manufacturer coisisted of receipts, transmitted from father to son, through successive generations, the result of accidental expe- 
rience, accumulated through ages, and receiving now and then an occasional impulse from some happy accident. Fortunately that period has passed, and now nearly all the 
improvements in the 



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may be traced to the laboratory of the chemical philosopher. The definite laws which govern the union of bodies, are now brought to bear on the processes designed to 
form the numberless products of the arts; and as a necessary consequence, we have established more economy in these processes, and greater precision and certainty in 
their results. 

Time has been when the manufacturer decried the study of theory with reference to its application to practical utility, but happily that time is rapidly passing away. 
In nearly all the great and flourishing establishments in Europe we" find that the chemist is not omitted, if his science can be of the least utility; and even in the smaller, 
some leading operator, if not the proprietor, is required to possess a full share of theoretic knowledge. The improvements which we daily witness in the useful arts bear 
too indelibly the seal of chemistry, are too intimately blended with chemical theory to admit of ignorance of these principles in any artisan whose operations are in tin- 
slightest degree tinctured with chemical changes. 

A knowledge of the science of Chemistry can no longer be regarded as an accomplishment by the artisan, but as an essential branch of his education. 

IN AGRICULTURE, THE ANALYSIS OF SOILS, OF MANURES, AND OF PLANTS 

themselves, the study of the chemical changes produced during the growth of the plant, and the means of operating chemically with the view of obtaining the highest state 
of luxuriance and the greatest profitable yield, are all of tooevident advantage to be overlooked by the skilful Farmer. 

The operations of the DYER and CALICO PRINTER bdng almost exclusively dependent on the laws of chemical combination and decomposition, must he studied as 
much from theory as from practice, in order to the successfulprosecution of these several important arts. Moreover, if we desire to improve and extend them, are we to 
proceed from a blind practice, and not rather from a knowledge of the action of the various bodies upon each other, in accordance v\ ith the known laws of chemical affinity > 
Some of the most important improvements in the various depigments of Dyeing and Colour Printing have originated from the experimental researches of the theoretic 

Why is it that numberless attempts in the reduction of MErALS FROM THEIR ORES, and in the subsequent processes of refining and reconverting them into new 
compounds, have so signally failed? It would seem almost impracticable to extract certain metals, such as Gold, Silver, Copper. Lead, Sec. from their ores, in the United 
States, with profit, unless these ores are far richer in yield th;«i similar mineral substances in Europe; and even in many of Ihpse which arc wrought with advantage, such as 
lead, iron, &c, the slags and other residues which our metalhrgists reject as useless, would often meet with successful treatment in the hands of a chemist who posse 
knowledge of theory with his practice. , ...... 

In the practical operations of the GLASS MAKER we arcalready pretty well skilled, and yet it is not long since the introduction of soda in connection with potash was 
found to be of advantage, both in respect of the quality of glass, and of economy in working it, although theoretic chemistrj h pointed it out. But even in this 

manufacture much remains to be done in regard to the" quality of the»material, in economy in its production, and in its various colours. 

Nor'does the Potter, the maker of brick and earthen-ware , require less knowledge of theoretic chemistry than any other artisan, since the character of the clay and flint of 
the glazing and his colours have been more fully developed and improved by chemical science. The oft repeated and long continued experiments to establish the fabrication 
of the finer kinds of Pottery, including Porcelain, would have been less frequently repeated, and proved more successful, had extended chemical knowledge been applied to 
them. 



We might continue to enumerate various important arts which have either originated from or have been improved by the pure science of chemistry, but we are pleased to 
find that the repeated calls of manufacturers for chemical hooks anil chemical knowledge, give evidence that they are beginning to perceive the vitality of this science to the 
fa] prosecution of their several arts; and we may confidently predict their improvement on principles which were developed in the laboratory. 
THE ENCYCLOPEDIA OF CHEMISTRY is designed to meet the varied wants of tire 

STUDENT OF SCIENCE, THE PHYSICIAN, THE AGRICULTURIST AND THE MANUFACTURER. 

1 he first and second will find the whole fheorv of chemistry fully developed, as contained in the original essays of all the great and leading chemists, among whom we place 
BERZBL1US, LIEBIG, AYOEHLER, ROSE, MITSCHERL1CH, ZE1SSE, &c, DUMAS, PELOUZE, FREMY, &c, GRAHAM, KANE, HARE, and many others in 
Europe and in our own country. They will find all the important recent discoveries in organic and inorganic chemistry, and practical treatises on the several branches of 
anali sis. 

T HE AGRICULTURIST will find, beside the essays on analysis with reference to soils, &c, frequent reference to the 

APPLICATION OF CHEMICAL PRINCIPLES TO AGRICULTURE, 

and to various crops which may be made available for the purposes of chemical manufacture. 

1 o the MANUFACTURER this work must prove most acceptable, since the application of scientific principles to the numberless branches of the arts will receive a large 
share of attention, and wherever it is deemed advisable ENGRAVINGS WILL BE GIVEN illustrative of the various processes of art. Beside the several treatises on 
the chemical arts which have appeared in England or the United States, we shall draw largely from the works of Berthier, Dumas, Payen, Karsten, Runge, Vitalis, and 
many others, who have enriched the useful arts with valuable treatises, either on all or many of their branches, with especial regard to the important application of chemical 
science. 

Beside the various subjects presented above, the 

will receive their full share of attention, more especially in their chemical relations, and where they admit of useful application. It will be seen from the hasty sketch of 

the design of the work presented above, that it is intended as a complete 

ENCYCLOPEDIA OF CHEMISTRY BOTH IN THEORY AND PRACTICE, 

and that while the pure theoretic nomenclature will be adopted in the one part, the second shall be so developed as to jring it within the reach of those not fully conversant 
with chemical principles. 

STerms. 

The work will appear in semi-monthly numbers, and in addition to Numerous Wood Cuts, will contain many Beautifully Engraved Plates, 
and will be completed in Twenty Numbers at 25 Cents each. 

Any person remitting $20 will be entitled to receive five copies. A liberal discount allowed to Booksellers and News Agents. 

CAREY & HART, Publishers. 

Philadelphia, May 30, 1S43. 



WAGNER'S PHYSIOLOGY, 

TRANSLATED FROM THE GERMAN. 

TO WHICH WILL BE ADDED NOTES AND REFERENCES 

BY SAMUEL JACKSON, M.D., 

rnoFESSon of the institutes or medicine in the univeiisity of pennstlyania. 



TODD AND BOWMAN'S PHYSIOLOGY, 

(TO BE COMPLETED IN THREE PAETS.) 

THE PHYSIOLOGICAL ANATOMY AND PHYSIOLOGY OF MAN 

WITH NUMEROUS ORIGINAL ILLUSTRATIONS. 

BY 

R. B. TODD, M.D., F.R.S., AND W. BOWMAN, F.R.S. 

OF KING'S COLLEGE, LONDON. 



GODDARD ON THE TEETH. 

THE ANATOMY, PHYSIOLOGY, AND DISEASES OF THE TEETH AND GUMS, 

WITH THE MOST APPROVED METHODS OF TREATMENT, INCLUDING OPERATIONS, AND A GENERAL ACCOUNT 
OF THE METHOD OF MAKING AND SETTING ARTIFICIAL TEETH. 

BY PAUL BECK GODDARD, M,D„ 

DEMONSTRATOR OF ANATOMY IN THE UNIVERSITY OF PENNSYLVANIA. 

In One Volume. 
Illustrated by about Thirty beautifully executed Plates, each containing Numerous Figures. 



VALUABLE WORI^S ON MEDICINE, SURGERY, CHEMISTRY, &„, &c, 

© A R H t 4 IH1AI1T, IPIHiaLAIPIlLIFIHIBA, 

HAVE IN PRESS, AND WILL SHORTLY PUBLISH, 

ELLIOTSON \ND STEWARDSON'S PRACTICE 



PRINCIPLES AiND PRACTICE OF MEDICINE, 

BY JpHN ELLIOTSON, M. D., F. R. S. 

President of the Royal Medical and Chirurgical Society; late 'Prnfoor of the Principles and Practice of Medicine, and of Clinical Medicine, and Dean of the Faculty of Medicine in University-Col- 
lege, London; late Senior Physician to the TJniversitytollege Hospital; Fellow of the Royal College of Physicians, and President of the Royal Medical Society of Edinburgh. 

Edited by Nathaniel Rogers, M. D. 

Member, and late President of the Hu^erian Society of Edinburgh, and Corresponding Member of the Medico-Chirurgical Society of Dublin; 
And ALEXj'NDER COOPER LEE, Esq., of University College, London. 

Greatly Enlarge!, Improved, and Adapted to the United States, 

Bf THOMAS STEWARDSON, M. D. 

Physician to the Pennsylvania Hospital, etc. 



PREFACE OF THE SF.COND IONDOS EDITION. 

When this work first appeared, it had to compete with everal long established favourites, and to encounter some deeply rooted prejudices on the part of men who 
strongly dissented from Dr. Elliotson's views on certain sujects. In spite of these obstacles, however, its reception has been more flattering than we dared to anticipate. 
The first impression was rapidly exhausted; it became the ivourite class-book in the majority of our medical schools; and even those who were formerly strongly preju- 
diced against it, have since acknowledged the practical infoihation they have derived from its perusal. All this is highly satisfactory; and were any additional proof of 
its sterling worth required, it would be furnished by the faclthat the Germans have published a translation. 

In entering on the task of preparing for publication a secod edition, we have been stimulated by the success of the first to fresh exertions, in order to render it (if pos- 
sible) still more worthy of the approbation it has received. With a view to the accomplishment of this object, we have ventured on making certain additions and alter- 
ations; which, without materially increasing the size of the bok, will (as we believe) materially enhance its value. Much care and discrimination were necessary in 
making these additions, — both as to the material to be selectd, and the mode of its insertion; otherwise the book would have been injured, rather than improved. We 
have therefore been careful only to remedy obvious deficiency, and to make such other additions as more recent researches had rendered necessary. The sources whence 
this supplementary matter has been taken are various; but w have of course been guided, to a great extent, by public opinion; — making our selections from those works 
which seemed best entitled to our confidence, for their genera accuracy and soundness of doctrine. For the purpose of rendering these additions as useful as possible, it 
has been deemed advisable to insert them within brackets, in \e text; — taking care, however, to preserve the continuity of the whole; and to acknowledge, in a foot-note, 
the source whence each quotation was derived. Some other lustrative extracts, often very interesting in a literary point of view, and all bearing on some medical obser- 
vations in the text, have been inserted as foot-notes. 

The alterations that have been made, though few, are such b have been dictated by a desire to consult the convenience of the reader. The subjects have been grouped 
together, in conformity with Dr. Elliotson's own views; and diided into parts, books, chapters and sections. Page-headings and side-titles have been introduced: which, 
together with a copious index, will (it is hoped) enable the reder to refer to any particular passage with perfect ease. We may also add, that the work has been printed 
With a smaller, though clear and distinct type; — for the purpoj of enabling us to add about two hundred and fifty pages of new matter, without materially enhancing the 
size or price of the book. 

These are the alterations we have deemed it necessary to mie. In the performance of our task, we have been actuated (at every step) by a sincere and ardent wish 
to render the volume worthy of the reputation which Dr. Ellioton has so justly acquired, both as a teacher and physician. In working out this design, we have received 
every assistance from the enterprising publisher, who has spared |o expense either in the literary or the printing department; — being anxious to raise this distinguished mem- 
ber of his series of medical text-books to a degree of excellence Commensurate with the favour it has received. Whatever approbation or censure maybe bestowed on our 
labours as editors, we feel quite certain that the valuable materia contained in this book, will always meet with the respectful consideration due to genius and industry, 
when directed to the alleviation of human misery. 

OPINIONS OF THE PHESS. 

Almost every subject exhibits great research and acumen, orignal and comprehensive views, and an extensive acquaintance with Physiology, Pathology, and all the 
known resources of the healing art. Some affections which arescarcely noticed in other works (such as Glanders, Hay-Asthma, &c.) are also considered; and there is 
much interesting detail connected with these topics. In additioi to sterling practical matter, in- which the work everywhere abounds, we have all the charm of varied and 
lively illustration; — drawn, not merely from writings strictly Medcal, but from the pages of History, Poetry, and general literature; so that the casual reader would be 
surprised to find many parts of the book as entertaining as a no^l: — for instance, Idiocy, Insanity, and other topics. The Doctor has not thought it necessary to be 
crabbed and technical, dry and repulsive. He has evidently strivin to render his subject inviting to his auditors, that he might win their affections and attention, and thus 
inculcate the more successfully the important truths he had to cotvey. We are also happy to bear testimony to the spirit of candour and fairness that the work exhibits. 

After a diligent perusal, we have formed the highest opinion a this edition of Dr. Elliotson's " Principles and Practice of Medicine." It is the most modern work on 
the subject; and is every way calculated to represent to foreignersthe present state of practical medicine among the best practitioners of our country. We think it 
unnecessary to recommend it; because it will recommend itself, aid command success by its own intrinsic merits. 

The Editor, Dr. Rogers, has acquitted himself in a very admirale manner; and we cordially assent to all that he claims in the Preface. He also deserves the negative 
commendation of not encumbering the text with multifarious note. Most readers prefer to judge and compare for themselves. We have only to add, that it forms a 
goodly volume, containing upwards of 1100 octavo pages, printed a a bold and clear type, and published at a very moderate price. — Medico-Chirurgical Rcvi, w. 

It is very gratifying to meet with a work replete with sound am valuable matter; — with golden rules of precept and practice, derived from the writer's long experience 
and observation; and in which all the resources of a well-cultivatedmind, are brought to bear upon and illustrate the subject to which its energies are addressed. Such a 
work is the one before us; in the production of which Dr. Elliotsonhas been induced to acquiesce, under the editorship of one who has proved himself well worthy of the 
office. 

We find some excellent preliminary observations on the means W which the art of medicine is to be perfected; followed by a copious introductory discourse, calculated 
to be of great use to the student. Our Author's exposition of infla|Lation is most excellent; and, though occupying upwards of eighty pages, we do not see a line we 
could " wish to blot." Immediately in connection with inflammati | come hemorrhage, profluvia, and dropsy; then change of structure, and new formations (as scirrhus, 
tubercles cancer, &c); which conduct us to those diseases termed r our Author " universal:" as anemia, chlorosis, scurvy, and fevers, (intermittent, remittent, and con- 
tinued.) All these topics are expounded with first-rate ability; and etray, in every touch, the hand of a master. The details connected with malaria, as a cause of ague, 
of contagion, and as a source of continued fever, are particularly copies, interesting and important. 

We regret that we have not space for copious extracts, from the vat mass of exceedingly important information contained in these pages; although we are thus saved 
the predicament of selecting from so much that presents equal claims kr insertion. The chapters on phthisis, and diseases of the heart, are worth the price of the entire 
volume; particularly since the Editor has supplied, either by notes or^ppendix, the cream and substance — the heart (we may say) — of Dr. Elliotson's well known and 
highly esteemed work on the latter subject. Dr. Rogers has also fujnshed a synopsis of Cullen's "Nosology;" some physiological and toxicological tables, by the late 
Dr. Fletcher; extracts from Dr. Elliotson's " Physiology," &c; and wf cordially award him our meed of praise, for his skill, vigilance, and fidelity. The volume altogether. 



considering that it relates to a subject usually accounted dry and technical, is remarkably inviting and interesti g. Whenever a topic will permit, it is enlivened with 
much brilliant illustration and racy humour. Indeed, many pages might be perused, even by a laic, with aviditjand interest, if not with advantage. The diction is 
simple, terse, and expressive; the style is vigorous and sententious;— sometimes colloquial, but always perspicious and flowing. On the whole, we have the highest 
opinion of its merits; and consider it decidedly the best, as it is the most recent work on the subject. As sua, we predict for it a standard reputation; and a very 
extended sale among the cultivators of practical medicine. Such a work ought to be in the hands of every practkoner who desires to fulfil the grand purpose of his voca- 
tion—the diminution of "the thousand ills that flesh is heir to,"— that noble study which renders medicine wU the ancients were wont to term it; — "ars divina, — a 
heaven-descended art." — Dublin Medical Press. 

It will be generally admitted, that to an extensive acquaintance with physiology and pathology, Dr. Elliotson mites the faculty of accurate diagnosis, and acute dis- 
crimination of the best methods of treating disease. Few, we think, will be disposed to question his zeal and acliity as a physician, and as a teacher of the principles and 
practice of medicine; or the judicious views, philosophical deductions, and sound methods of treatment here enveiped. Almost every page teems with valuable informa- 
tion. The details connected with insanity, and some other topics, are so illustrated and enlivened by curious facs from the writings of poets, historians, and philosophers, 
as .to render them highly entertaining, apart from the important practical matter with which they are interwover Much praise is due to the Editor, for the exemplary 
manner in which he has acquitted himself. He has not overloaded the text with superfluous notes; but has apended just so much as was necessary for the purpose of 
illustration, and to fill up some hiatus. He has also considerably improved the language. We strenuously reccamend the work to ail who feel interested in the advance- 
ment of Practical Medicine. — London Medical Gazette. 

The Author has been long honourably distinguished as standing in the foremost rank of those who have forrcd a corps of observation for the purpose of exploring the 
recesses in which those terrible foes of the human race, phthisis and its allies, had hitherto reigned in almost unisturbed dominion. His language is simple and nervous, 
and remarkably free from technicalities, and inflated epithets; while his style is of that pleasant, familiar kind — nether too bold, nor too florid — which accords well with the 
subject, and the occasion. The medical world is under great obligations to Dr. Rogers, for having undertakn the editorship of this work. He has evidently bestowed 
gTeat pains in amending the text, correcting reporters' mistakes, and supplying deficiencies; — in every way prring himself a faithful Achates. We cannot entertain a 
doubt, that this work — embodying as it does, the mature experience of an able and accomplished physician — wil be welcomed by all classes of the profession. We predict 
for it a wide circulation, and the warm encomium of every one who becomes possessed of it. Less than this«vill not be commensurate with its high deserts. — Dublin 
Journal. 

The best work for the study of diseases, is " Elliotson's Practice of Medicine," by Rogers. — Lancet. 

COMPANION" TO QTXAIIT'S ft.WA.IOMY. 

OPERATIVE SURGERY; 

OR, A DESCRIPTION AND DEMONSTRATION OF THE VAIIOUS PROCESSES OF THE ART, 

INCLUDING ALL THE NEW OPERATIONS, AND EXHIBITING THE STATE ff SURGICAL SCIENCE IN ITS PRESENT 
ADVANCED CONDITION: WITH SEVENTY PLATES, COMPRISING UIWARDS OF ONE HUNDRED AND 

FIFTY SEPARATE ILLUSTRATIONS. 

BY JOSEPH PANCOAST. M. D., 

PROFESSOR OF GENERAL, DESCRIPTIVE, AND SURGICAL ANATOMY IN JEFFE1SON MEDICAL COLLEGE, PHILADELPHIA: 
LECTURER ON CLINICAL SURGERY AT THE PHILADELPHIA HOSPITAL, ETC., ETC. 



PROSPECTUS. 

That no one branch of science has made more rapid advancement in modern times than Operative Surpry, has become an axiom which has passed eren beyond the 
limits of the profession. The class of ancient and important operations, such as those for cataract, sbne, amputation, and strangulated hernia, has latterly, by men 
imbued with a profound knowledge of anatomy and surgical pathology, been subjected to the most rigoros and patient investigation. Among the processes described for 
their performance, which have been so numerous as to embarrass the learner, those that have proved the lost certain and satisfactory in their results have been carefullv 
pointed out: and such new ones have been instituted as the advance of the science demanded. 

But the activity of the present generation of surgeons has gone beyond this, and the enthusiasm whichhas been displayed by it in the improvement of the science has 
been attended with a success that has surpassed all expectations. The most happy means have been mde known of relieving deformities and curing a numerous train 
of'diseases which till lately were believed to be beyond the resources of the art, or susceptible only of sore palliation. Without counting lithotrity which has supplanted 
to so great an extent the practice of cutting for stone, staphyloraphy and a crowd of other operations wSch have become established in the profession, some new depart- 
ments of the science have been created, which are now rapidly undergoing development, and to which t'e term la soitiuj. chikuhgie has been applied. To this 
spirit of enterprise we owe the introduction of the various ingenious processes for the cure of club-foot ad other contractions about the joints by the section of muscle 
tendon and fascia, as well as the extension of the new plan of subcutaneous operation to the division ofsphincters — the reduction of dislocations— the removal of mere 
muscular distortion — the cure of empyema — the various processes for the removal of strabismus — the rstoration to their original shape of parts that have been lost or 
deformed through disease by plastic operations, and the different propositions that have been made for tie cure of stammering and myopy by surgical measures. 

That there has been from the love of novelty a multitudinous invention of processes — that many ne\ operations have been suggested which have not and will not stand 
the test of sober experience, and that it has become necessary to narrow down the list by a careful pruring away of many, which are useless or hurtful, is no more than 
was to be expected. Under this new aspect of things, it is believed that a complete series of surgical Irawings, carefully chosen, so as to represent fairly the science in 
its present advanced state, with the plan of operations concisely given in the text, will meet the wishes >f the profession in this country, where from choice or necessity so 
large a number of practitioners are called upon to practise surgery. The German student can turn ir the model of an operation to the large and extensive works of 
Bierkowsky, Froriep, and Giinther; the French to the splendid production of Bourgery and Jacob; butthe English and American student can find no completely illustrated 
work on Surgery in his own tongue. The monograph treatises of the kind which have issued from tb English press, limited as they are in their range, are too expen- 
sive to come into general use. Yet without accurate and well finished plates, the various methods ofiperation can be but imperfectly understood by the learner and the 
more experienced practitioner feels their need in refreshing his memory of what had been partially fogotten. It is to supply this want that the present work has been 
undertaken; and that it may be the more useful, it will be furnished at a price within the means of ahost every member of the profession. The best artists that can be 
procured in the country have been employed upon the plates. The work will be published in large uarto form, the size of Quain's Anatomy, and will consist of about 
70 plates, comprising a gTeat number of separate drawings, with from 200 to 250 quarto pages ofdescriptive text, the whole intended to form a coin rile te work P^hi 
biting the OPERATIVE SURGERY of the day. p orK exm ' 

£erms of ^utJltcatfjm, 

The Work will be completed in one splendid Royal Quarto Volume of from 200 J250 pages of LeUer Press Description, and about 

Seventy Splendidly Execiitea Plates, 

many of which will contain several Figures, and will be executed with the gro/test care, by P. S. Duval under the direction of 

PROFESSOR PANCOASuj 
The Price of the work, neatly bound in Cloth Lettered, will be TE]S(i)OLLARS a copy, payable on delivery. 
As specimens of both Letter Press and plates are appended, it is of course unnecessary for the ^Wishers to say more than the entire work will be found to corr i d 
in every respect with the specimens. r i CAREY & HART, Publisher^ " 

q3» Persons desirous of subscribing to this work are requested to address CAREYS HAR r JdPublishers, Philadelphia, (post paid,) enclosing ten dollar • 







///nh.., />////.,■/• ,/ /,, 



(?fi*4?S&t ^~ 



A SERIES 



OF 



ANATOMICAL PLATES; 

WITH REFERENCES AND PHYSIOLOGICAL COMMENTS, 



ILLUSTRATING 



THE STRUCTURE OF THE DIFFERENT PARTS 



THE HUMAN BODY. 



BY JONES QUAIN, M.D. 

PROFESSOR OF ANATOMY AND PHYSIOLOGY IN THE UNIVERSITY OF LONDON. 



AND 



W. J. E. WILSON, M.D. 

LECTURER ON PRACTICAL AND SURGICAL ANATOMY AND PHYSIOLOGY. 



jScconfo (Kfottton Hnnaeir, toitl) 2Uiutional Jfotcs, 
BY JOSEPH PANCOAST, M.D. 

PROFESSOR OF GENERAL, DESCRIPTIVE, AND SURGICAL ANATOMY IN JEFFERSON MEDICAL COLLEGE OF PHILADELPHIA, 
LECTURER ON CLINICAL SURGERY AT THE PHILADELPHIA HOSPITAL, ETC. ETC. 



PHILADELPHIA: 

CAREY AND HART, CHESNUT STREET, 

FOR G. N. LOOMIS. 

1S43. 




Entered according to act of Congress, in the year 1842, by Carey & Hart, in the Clerk's Office of the District Court of the 

Eastern District of Pennsylvania. 



STEREOTYPED BY L. JOHNSON, 
PHILADELPHIA. 



PRINTED BY C. SHERMAN. 



ADVERTISEMENT 

TO THE AMERICAN EDITION 



The American publishers of this work, for the purpose of rendering it more extensively useful by bringing 
down the price so as to place it within the reach of almost every one interested in the study of Anatomy, have 
reduced it from the folio to the quarto form. By this means, it is believed, the work will more than repay what it 
loses in magnitude and pretension by the greater convenience and facility for reference that it will afford the 
student. In usefulness and accuracy, the American publishers consider this will be found in no respect behind the 
English edition. Portions of the body which are minute or complicated in structure, as the organs of the senses, 
the head, brain, &c, are represented of the same size as in the original edition, whilst such drawings as were too large 
for the quarto form have been reduced to the requisite size, with care to observe as far as possible the proper propor- 
tion of the different parts. The figures have been in general carefully compared with the original sources referred 
to in the advertisement to the London edition, and especially with the recent extensive work of Messrs. Bourgery 
and Jacob, from which many of the English copies have been drawn. Considerable attention has been given to the 
correction of the references to the plates, which almost necessarily in a work that has had to pass through so many 
hands, and where the references are so numerous, must be found more or less defective. Many synonyms and 
additional references have been introduced without mark through the body of the work, for the purpose of rendering 
it more useful to the American student, whilst the text of the accomplished English anatomists, Messrs. Jones 
Quain and W. J. Erasmus Wilson has been published without abbreviation. It has not been the desire of the 
American publishers to have the work loaded with notes, but such have been added as it is believed will render the 

work more useful to the students of this country. 

Joseph Pancoast. 

Philadelphia, August 1, 1842. 



ADVERTISEMENT 

TO THE ENGLISH EDITION 



This publication consists of a series of the most approved Anatomical Drawings, selected from monograph 
treatises or from systematic works. The highest place in the former class is deservedly conceded to the works 
of Scarpa and Tiedemann, and in the latter, to those of Mascagni and Caldani ; but, from their size, and the style 
in which they are executed, the expense of publication is necessarily such as to confine their usefulness to 
comparatively few persons. It may, however, be fairly admitted, that the collections of Cloquet and Loder, though 
not of equal pretension, are no less valuable to students, as a guide to the knowledge of that complex fabric, whose 
composition they seek to investigate; and to those of maturer age, as a means of reviving impressions received 
during their earlier studies. As, however, even the works last named, from their price, are inaccessible to some, and 
to others from the descriptions and references being given in a foreign language, the want of a similar publication 
in an English garb has been for some time complained of. 

• To supply the want here noticed, and at a moderate price, is the object of the present undertaking. The plates 
are accompanied by letter-press, containing detailed references to the various objects delineated, the names being set 
down in English, Latin, and French. But with a view to render them intelligible to a greater number of persons, 
a running comment on each Plate is given, stating in general terms, and divested (as far as can be) of all tech- 
nicality, the uses and purposes which the different objects serve in the animal economy. The drawings are taken 
on stone by Mr. W. Fairland, and the printing executed by Hullmandel, and Graff and Soret. 

The work consists of Five Divisions, as follows : 

The Bones and Ligaments. 

The Muscles. 

The Heart and Blood Vessels, (Arteries and Veins,) with the Lymphatic and Lacteal Vessels. 

The Brain and Spinal Marrow ; the Nerves and Organs of Sense. 

Organs of Digestion, Respiration, and Secretion. 



IV 



THE 



BONES AND LIGAMENTS 



OF 



THE HUMAN BODY. 



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,jh St'""' A' & '■ ' /'""i" 



r7n/n'/r/p/"<> TuAbaJtset bj/ Carey 4 Mart 



/' S /)/,,„/ CiJj, 



OSSEOUS SYSTEM. 



The Osseous System (systeme osseux, ossa, o«t») is peculiarly fitted, by its solidity and hardness, not only to give support 
to the soft parts, but also to furnish points of attachment to the muscles, by which the different movements are executed. This 
solid frame-work of the body is made up of a number of separate pieces, the aggregate of which has been termed " the skeleton." 
It is a favourite opinion with some persons, that bones determine the form of parts, as well as the direction of the body. But we 
find, that in their developement they just keep pace with that of the soft parts, particularly of the central nervous masses. If these 
proceed regularly to their completion, so will the arches of the vertebrae, and the bones of the head ; but, if their growth be 
retarded or deranged, the bones will not arch inwards, and so the spinal and cranial cavities will remain open. Again, if we 
descend through the series of animals, the skeleton becomes gradually more simple and rudimentary, until it is reduced to its 
fundamental part— the spine ; and even this may be composed of cartilage, with scarcely a trace of calcareous matter. A few 
grades lower down in the scale, we find multitudes of animals altogether destitute of a skeleton, either internal or external, so that 
the muscular structure alone remains as the means of locomotion. Bone is, then, the passive instrument — muscle the active agent ; 
muscle is, moreover, prior in its appearance and importance in the animal series, bone being secondary in both respects. It maybe 
asked, are we still to persist in drawing such a broad line of distinction as has been hitherto done, between the hard calcareous parts 
of Crustacea and insects, and the osseous system of higher animals, as that the latter alone should be considered to merit the name of 
skeleton, whilst the former is treated as a mere shell, or outward tegument? To put the question in a different way, is it more 
conformable with what we know of the economy of nature — is it more philosophic, to admit, at once and without examination, 
that these so-called shells or crusts are altogether new organs given to the animals they invest, (and as such destitute of any 
analogy with the structures observed in higher grades of beings, and with which we are in general more familiar,) or to scrutinize 
these different parts attentively, and carefully note the points of similitude, if any, which may exist between them, with a view to 
determine whether they are not really modifications, or repetitions, of what occurs in other tribes, and so trace out (what analogy goes 
a great way to establish) a unity of plan throughout the animal series ? The researches of Geoffroy Saint-Hilaire and others have 
thrown much light on this important question. The mere position of parts, whether internal or external, is a matter of little moment ; 
a consideration of their structure, and adaptation to purpose and use, can alone determine whether any correspondence exists 
between them. The internal skeleton of a vertebrate animal, and the external one of the articulata, appear to be really analogous 
parts in the economy of these classes of animals, notwithstanding the vast distance which separates them in the scale of being; 
and the difference, though confessedly a considerable one, which exists between the rachis of a crustaceous animal and that of a 
fish, reptile, bird, or quadruped, seems to arise from the circumstance that a spinal marrow exists in the one, but not in the other, 
a special conformation of the osseous system being required in each case. 

Situation. — The osseous structure is situated deeply, being covered by the soft parts and common integuments ; at least, this 
is the case in the vertebrate animals. 

The number of bones is differently stated by writers, the difference arising from the period of life at which the enumeration 
is made : in early age the number is greatest, and subsequently diminishes, when, by the process of ossification, two or more 



PLATE I. 

Skeleton of an adult male, anterior aspect. This figure is copied from Cheselden's beautiful plate. In li is description of the figure, 
Cheseldcn observes that it is "in the same proportions and attitude with the Belvidere Apollo." 

3 



previously distinct pieces become united into one. Their form and size present a considerable degree of variety. ley ai 
usually divided into long, short, flat, and mixed. 

The long or cylindrical bones belong in general to the parts intended for locomotion, and represent so many levers, to e 
moved by the muscles in various directions. When examined from the superior part to the inferior, viz. from the humerus 
femur, to the phalanges of the fingers or toes, they are found to increase successively in number as they diminish in size— a is- 
position which gives to the superior division of each limb the great extent of motion it enjoys, whilst it allows to the inferior an 
terminal ones a variety of rapid movements within restricted limits. 

Each long bone presents a body, or middle part, and two extremities. The shaft or body is round and cylindrical in some, 
prismatic in others, but somewhat bent or twisted on its axis, so that the direction of its superior extremity does not exactly corres- 
pond with that of the inferior. Whatever difference of outward form may obtain, there is little or none in that of the internal canal ; 
it is circular in the tibia as well as in the femur. This canal is not intended merely to lodge and protect the medulla ; it contributes 
very much to increase the strength of the bone, as has been satisfactorily shown by direct experiment. If two cylinders contain 
the same quantity of matter, one being solid, the other hollow, the power of resistance of the latter is greater than that of the 
former, owing to its greater diameter. By this conformation, also, bones, without being increased in weight, require an adequate 
degree of lightness, together with sufficient superficial extent to afford a more expanded surface for the attachment of muscles, which 
are important requisites in what may be considered as the passive organs of locomotion. 

The short bones are usually situated in parts in which solidity and firmness are required to be combined with freedom of 
motion ; for instance, in the carpus, tarsus, and vertebral column. Their external conformation is necessarily influenced and 
determined by that of the parts into whose composition they enter ; and as they are intended to co-operate in certain common 
functions, they present a number of articulating surfaces, prominences, and depressions, suited to their mode of adaptation and 
mutual connexion. 

The flat or broad bones for the most part serve to form the walls of cavities, or to enclose spaces. They present two surfaces, 
one convex, and the other concave ; which conformation, by giving them an arched form, increases their power of resistance, and 
affords additional security to the organs they enclose. The bones of the skull and pelvis come under this denomination. 

Some are so irregular in their form as not to be referrible to either of these heads. These are situated along the median line, 
as the occipital, the sphenoid, and ethmoid bones, and the vertebrae. 

In addition to these divisions into classes, adopted by all writers, those who treat expressly of descriptive anatomy are 
obliged to have recourse to others. Thus, in order to facilitate the description of irregular bones, such as the ethmoid, or the 
sphenoid, they are considered as being divisible into a central part or body, and processes ; the anatomical situation of the parts 
forming the ground of division. In other instances it is supplied by the mode of developement, as of the os innominatum into 
ilium, ischium, and os pubis. Finally, in some, the division is founded on the situation and relations of their parts, as when the 
frontal bone is resolved into a frontal, nasal, and orbital portions. 

The surfaces of bones are marked by eminences and depressions adapted to various purposes. The eminences may be 
ranged under four heads. 1st, those of articulation ; 2nd, insertion : 3rd, impression ; 4th, reflection. Those for articulation vary 
according as they are movable or immovable, and shall be described in the next chapter. Those for insertion are variously 
adapted for the attachment of muscles, or for tendons and ligaments. They present numerous differences in their degree of 
projection, according to the sex, age, and muscular developement of each individual. Their form is equally various ; some con- 
sisting of diffused asperities, others extending along the surface like rough lines, whilst others project more or less from the bone, 
and are intended not only to give insertion to muscles, but also to serve the purpose of increasing their power of action, by removing 
their line of direction farther from the axis of the bone. 

The eminences of impression are certain prominent lines interposed between depressions on the surfaces of bones. Thus, 
the shallow pits on the cranial bones corresponding with the convolutions of the brain, and the depressions on the external surface, 
marking the insertion of muscles, are separated by prominent lines, termed eminences of impression. The expression appears 
not to have been well chosen ; it was originally founded on the supposition that the action of contiguous organs, by depressing 
certain parts of the surface of the bone, served to elevate others ; but it is far more conformable to what occurs in other structures, 
to refer to the laws of nutrition and growth (by which different parts are mutually adapted to one another) the inequalities here 
alluded to, as well as those more prominent points to which muscles are attached. The latter are usually attributed to the action 
of the muscles drawing them out, and as it were moulding them ; but, as Bichat observes, such an opinion, founded on what 
occurs in soft and inorganic substances, ill accords with the known phenomena of vitality. We observe eminences for the inser- 
tion of ligaments, which project more than those which give attachment to muscles; for instance, the spinous process of the 
ischium; there is, moreover, no proportion between the elongation of different apophyses, and the power of the muscles attached 
to them, viz. between the styloid process of the temporal bone and its muscles. 

The term or phrase "eminence of reflection," is not often used. It expresses a fact which we occasionally observe, viz. that 
tendons slide upon elevations at the ends of bones, by which their direction is changed. As an instance, we may cite the case of 



the peronei muscles, and the flexors, which run behind the malleolar projections of the tibia and fibula, by which these tendons 
take a new direction, and modify the line of traction of their respective muscles. 

The prominences on the surface of bones are variously named, according to their form, degree of elevation, and the uses 
which they serve. When of considerable size, they are called apophyses, (processus, apophysis, a,-to from, <j>v,uc to grow.) These, 
in most instances, are appendices to the body or shaft of long bones, in infancy and in early life, when they are called epiphyses ; 
but as the process of ossification proceeds to its completion, they become, as it were, soldered to the rest of the bones. The term 
tuberosity (tuber) denotes an eminence, rather broad and rough, but not much projecting; tubercle (tuberculum) expresses some- 
thing still smaller. A process which is thin and tapering, is called styloid, from its resemblance to the Roman writing instrument, 
(stylus.) A sharp thin projection is called spine, (spina.) But one which runs along like a ridge, is called a crest, (crista.) An 
apophysis, when rounded, is usually called a head, (caput,) and the constricted part supporting it represents its neck, (cervix, col- 
lum.) Condyle is a compressed apophysis, which forms part of an articulation. 

The depressions and cavities on the external surface of bones are divisible into the articular and non-articular. The former 
shall be treated of in the section on articulations; the latter, being very numerous, may be ranged under the following heads. 
1st, those for insertion ; 2d, for reception ; 3d, gliding ; 4th, transmission ; 5th, nutrition. Those for " insertion" are well adapted 
for the attachment of muscle, ligament, &c, by increasing the extent of space allotted for that purpose, inasmuch as a concave 
surface presents a greater extent than a plane one bounded by the same line. Some of these, as the digastric and pterygoid fossae, 
by the greater depth at which they allow the muscles to be inserted, increase their power, by permitting an elongation of their fibres. 

The bones of the skull and face present several instances of "cavities of reception." Some correspond with the whole 
extent of a bone, as in the case of the parietal bone. Some occur in a particular part only, as the fossa in the nasal process of the 
superior maxillary bone, and os unguis for the lachrymal sac. 

The depressions for "gliding" are situated about the heads of long bones, being grooves, in which tendons slide, as they pass 
to their destinations. The formation of these has been attributed to the influence of the mechanical pressure and friction of ten- 
dons. But such a rationale is inadmissible ; for they are found in subjects paralytic from infancy, and are by no means propor- 
tioned in depth to the force of the muscular exertion which bears upon them. The different configuration of bones should rather 
be considered as the result of the laws of ossification which preside over the growth and developement of the osseous system, and 
by which its different parts are adapted to their appropriate purposes. 

The cavities for " transmission" give passage to vessels and nerves ; their form is various, some being mere fissures, others 
tubular, &c. ; to this head are referable most of the apertures at the base of the skull. 

The foramina of "nutrition" transmit the vessels intended for the support of the substance of the bones and of the medulla ; 
they are divisible into three orders. The first usually receive the name of foramina of nutrition, though in strictness it docs not 
belong to them more than to the others, the only difference between them being, that they transmit vessels to supply the medullary 
membrane, whilst the others give passage to those which are distributed to the substance of the bone. The first set, considerably the 
largest, are situated towards the middle of the long bones, and penetrate their substance in an oblique direction. The second 
order of foramina are much smaller, but very numerous; they are most perceptible towards the extremities of long bones, and 
generally all over the surface of the short and thick ones. But the third are so minute as to be perceptible only by the aid of a 
glass, by which we can discern them all over the surface. 

The depressions and cavities in bones differ so much in form, size, and use, that it has been deemed necessary to devise cer- 
tain terms to mark these differences. A deep pit which receives the globular head of a bone, is called a cotyloid, or cup-shaped cavity, 
(xotvxri a cup,) or an acetabulum, (an ancient cup or measure,) ex gr. the socket which receives the head of the thigh-bone. If 
shallow and superficial, it is said to be glenoid, (-/M^ a shallow pit;) the articular surface of the scapula upon which the head 
of the humerus plays, is an instance. A large hollow or cavity in the interior of a bone, is termed a cave, (antrum,) such as that 
seen in the upper maxillary bone; when of a size smaller, it is known as a hollow, (sinus,) as in the body of the sphenoid bone ; 
and if still smaller, as a cell, (cellula,) as in the orbital process of the palate bone. A small depression is a fovea or fossa. The 
meaning of the terms canal, (canalis,) fissure, (fissura,) notch, (incisura,) and groove, (sulcus,) is sufficiently obvious. 

Structure. — The proper structure of bone is fibrous in its character ; the fibres, in some parts, by being closely aggregated 
together, constitute a firm and compact substance; but in others they lie so far apart as to enclose spaces or cells, on which 
depends the porous and spongy appearance of some bones. 

The compact substance is so close in its texture, that the naked eye can discover no interstices in it ; yet by the aid of a 
microscope a great number of minute vascular canals become perceptible. In the long bones, these canals are all longitudinal, and 
maintain a communication laterally with the great medullary canal, and externally with the vessels on the surface of the bone. 

The spongy or cellular part presents a multitude of spaces, of various forms and size, all of which communicate with one 
another, as may be proved by the following experiment; if the end of a long bone, or the surface of a fiat one, be perforated, 
and some mercury poured in, it will be found not only to descend through the cells, but also to flow out through the vascular 
foramina on the surface. The interior of flat and short bones, then, does not ditl'er so decidedly from that of cj lindrical ones, as 



would at first sight appear. Each presents a cavity, which, at least in the one towards its centre, is a hollow tube, but in the 
other is divided by a number of intersecting laminae, into minute spaces communicating freely with one another. 

Some peculiarities are observable in the arrangement of the compact and cellular structure in the different classes of bones. 
The body of long bones consists chiefly of compact substance, but the inner side of the tube is rendered rough by projecting 
filaments and lamellae ; towards their extremities, the compact substance is gradually reduced to a thin lamella, or layer, encasing 
the bone, the interior of which consists altogether of cells communicating freely with the central cavity. 

The two surfaces of the broad and flat bones are compact in their texture, the interval between them being made up of 
areolar or spongy substance. This is usually called diploe. In its original acceptation the term diploe' {hm%o 0i double) was 
applied to the two plates or tables of the cranial bones, together with the intervening cellular structure ; subsequently it was 
restricted to the latter part alone ; but it is now commonly extended to the loose tissue of all broad and flat bones. The internal 
table of the cranial bones is more dense than the external, and, from being also more thin and brittle, it is called vitreous, (tabula 
vitrea.) The short bones are made up for the most part of spongy substance, encased by a thin lamella of compact tissue. These 
differences arise altogether from the mode of aggregation and arrangement of the osseous particles ; for, on examination, the 
composition of both is found to be the same, being made up of the same elements, viz. a cellular base, in the areolae of which is 
deposited a peculiar earthy salt. 

These constituents may be separated, so that each may be examined by itself. If a bone be macerated for some days in a 
dilute acid, the saline or inorganic part is removed, whilst the organic remains ; the bone is thus rendered soft and flexible, but 
retains its form, its weight being diminished in proportion to the quantity of saline matter taken up by the acid: when reduced to 
this state, it presents no appearance of any particular arrangement of fibres, but by a continued maceration in water it may be 
resolved into layers, each of which will be found to consist of a series of fibres aggregated together. If the process be still con- 
tinued, the fibres become swollen and softened, and present an areolar texture, analogous to that of cellular tissue in other parts 
of the body. This then may be considered as forming the nidus for the deposition of that inorganic substance on which the 
solidity and firmness of bone depend. If a cylindrical bone be examined in this way, its central portion is found to consist of 
several laminae, super-imposed one on the other : the external one is continuous throughout its whole extent, forming its general 
envelope ; but those subjacent to it, as they pass from the centre, become gradually thinner, and turn inwards towards the axis 
of the bone, becoming continuous with the lamellae which divide it into areolae or cells, (cancelli, lattice-work.) In the flat and 
irregular bones, the compact structure which encloses them externally sends off filaments and plates to divide their interior 
into cells. 

Examined beneath the microscope, bone is seen to be composed of lamellae, which are concentric in long, and parallel in flat 
bones. Between the lamellae are situated numerous small longitudinal canals, and minute oval corpuscules. The longitudinal 
canals, named, after their discoverer, " the canals of Havers," contain medullary substance and vessels, and communicate with 
each other. They also communicate with the medullary canal in the shaft, and with the cells of the cancellous structure in the 
extremities of long bones and in the interior of flat bones. The canals of Havers are surrounded by minute concentric laminae 
and the latter appear to be crossed by delicate lines which radiate from the area of the canal, to the circumference of the concen- 
tric laminae of each canal. These lines were first observed by Deutsch, who imagines them to be tubes of a prismoid form, and 
filled with the calcareous substance of bone. In the extremities of long bones, in short, and in flat bones, the cells are the repre- 
sentatives of the Haversian canals, and are analogous in structure, being each surrounded by concentric lamellae. In like manner, 
the medullary canal of long bones may be regarded as analogous to one of these Haversian canals, and as representing one of 
these tubes exceedingly dilated. The oval corpuscles discovered by Purkinje are minute cells, measuring in their long diameter 
about g^th of a line. From the surface of these cells are given off a number of radiating and branching tubuli, which anastomose 
with the corresponding tubuli of neighbouring cells. The tubuli were first accurately described by Miiller : their larger trunks are 
about 7 oV o th °f a nne m diameter ; they are, nevertheless, very distinctly seen by means of the microscope. The cells of Purkinje 
and these tubuli are filled with calcareous substance ; hence they have been most appropriately named calcigerous cells and tubuli. 

By long-continued boiling, as is well known, a large part of the animal matter of bone is extracted, and a solution obtained, 
which concretes on cooling into a gelatinous mass. Again, if a bone be exposed to heat so as to expel all the animal matter it is 

PLATE II. 

Skeleton of an adult male, posterior aspect; after Cheselden. In describing this figure, Cheselden remarks that it was delineated from 
» the skeleton of a man five feet and a half high ; the left hand resting on the hip of another skeleton, which was near eight feet 
high." The latter represents a posterior view "of some of the bones of the lower limb of a man near eight feet high." The 
skull lying upon the ground he states to have belonged to the same man. 

In introducing the bones of the lower extremity in the position represented in the plate, Cheselden seems to have evinced a desire of 
directing the attention of the student to the obliquity of the femur in relation to the tibia ; in order to explain in this way the reason 
for the greater length of the inner than of the outer condyle. 



/'/fr/t :' 








OvStfi,,, /,< 1 1/,,/n. 



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rendered brittle and light, but still retains its form; but if the heat be raised until the bone becomes red, it undergoes a semi- 
fusion, as occurs in other earthy substances under the same circumstances. The analysis of bone affords the following results : 



According to Fourcroy and Vauquelin. 




Animal matter - 


51 


Phosphate of lime .... 


- 37-7 


Carbonate of lime - 


10 


Phosphate of magnesia - . - 


- 1-3 




100 



According to Berzelius. 




Cartilage .... 

Blood-vessels - 


- 


3217 
- 1-13 


Fluate of lime ... 


- 


2 


Phosphate of lime - 
Carbonate of lime - 




- 51-04 
11-30 


Phosphate of magnesia 




- 1-16 


Soda, muriate of soda, and water 




1-20 




100 



The general rules of these analyses serve to show that the fibrilte into which bone may be divided by maceration, consist of a 
cellular tissue, containing in its areolae a quantity of earthy salts. 

Respecting its ultimate fibre, several fanciful notions have been entertained by different persons. Thus it was considered 
by some to consist of absorbent vessels, filled with phosphate of lime. Others thought it to be made up of lamellae and fibres, 
between which was interposed an osseous juice, &c. Such gratuitous assumptions serve no other end than to lead inquiry out of 
the true path, and to retard, instead of promoting, the progress of useful knowledge. 

Process of Ossification. — Of all the systems of organs, the osseous is that which arrives latest at its full period of deveiope- 
ment, the progress of ossification not being fully completed in the different parts of the skeleton until about the sixteenth or 
eighteenth year ; sometimes even still later. From its first commencement to its final completion, the ossific process runs through 
three distinct states or conditions, viz. the mucous, cartilaginous, and, finally, that of solid bone. But though these succeed one 
another regularly, it would be a mistake to suppose that the mucous becomes hardened into cartilage, or the latter solidified into 
bone, by any process similar to transformation ; the facts observed by no means warrant such an inference. The change 
coincides with an alteration in the mode of nutrition in the part, in consequence of which bone is deposited in place of cartilage." 

The embryo, at the earliest periods in which it has been examined, presents no distinction of parts, all being equally soft and 
homogeneous. So, at least, it has appeared to the greater number of those who have investigated the subject. Sir E. Home, 
however, states that certain parts are distinguishable, even so early as the eighth day after conception. Towards the fourth week, 
the consistence of the parts corresponding to the future skeleton is sufficiently increased to admit of their being distinguishable 
from all others, and their outline defined. The vessels, at this period, convey and deposit gelatine, the basis of the cartilaginous 
state, which appears to be completed about the eighth week, for it is about this period that the depesition of bone begins in some 
places. The cartilages being temporary substitutes for bone, differ from it in many .respects. They present no appearance of 



* With regard to the manner in which the cartilaginous mould of a bone undergoes that modification of structure by which bone is formed, we have not 
yet, notwithstanding the labour of the microscopists, a perfectly clear or satisfactory explanation. The following account of cartilage and its changes v. ill 
briefly display all that is as yet known upon the subject. The cartilage of bone, (temporary or ossific cartilage,) though much resembling, is not perfectly the 
same as the cartilages, or fihro-eartilages, which are to remain in general flexible during life. The cartilage of bone, previous to the commencement of ossification, 
yields only, after long boiling in water, a substince called chmdrin, which differs from gelatin in not being precipitated by tannic acid, and in L r i v 'iu£ precipi- 
tates with salts which do not disturb a solution of gelatine, such as acetic acid, alum, acetate of lead, and protosulphate of iron; whilst the perfectly formed 
elastic and fihro-eartilages yield only gelatine when subjected to the same process, or gelatine with hut a minute portion of chondrin. The original chemical 
constitution of all the cartilages is thought to be the same. Their primitive physical formation is cellular, like that of other tissues of the body: between 
cells there is interposed a hyaline, or transparent intercellular substance, and the cells themselves are filled with a softish, granular matter. As the cartilage 
increases in growth, new cpIIs are developed in the hyaline substance, by which the older ones are pushed farther and farther from each other. The original 
cells produce two or more young or secondary cells from their granular nuclei ; between these secondary cells is also formed a secondary hyaline substance, 
and thus the original cells form each one a little group of cells enclosed within it, and each group is known under the name of cartilage corpuscle. 

The fixed character of the cartilage depends upon the ulterior developement in it. If fibro-cartilage be formed, the intercellular or hyaline substance is 
developed in the form of fibre, and the cells disappear altogether. If elastic cartilage, the fibres are developed around the cells, forming a kind of net-work. 
If ossific cartilage, a new set of corpuscles are developed in the secondary hyaline substance, called bone corpuscles, which are the nuclei of the bone cells, 
of which the microscope has shown all bony structure in reality to consist. As this process is going on, the cluster of cartilage cells called cartilage eorpn 
become compressed together: the secondary hyaline substance becomes dissolved and transudes through the walls of the primary or parent cell. It 
and, in this state of cytobkutema, constitutes the proper ossific cartilage. In it arise the bone corpuscles cylnblasts, from which are formed the bone cells. These 
follow the same mode of developement as the embryonic cartilage cells ; that is, new cells are forming in the eytoblastema. while tbosp recently produced are 
growing; the cartilage corpuscles, ever more closely compressed together, disappear; radiated points, nutrient vessels, &c, make their appearance; the 
nuclei of the bone cells acquire all the while calcareous sails, and become opaque; the bone cells themselves appropriate salts of the same kind, and the 
formation of bone is achieved. It is, according to this, from a peculiar substance, not ordinary cartilage, that bone is produced ; and we well krow that the 
effused fluid of which the callus in fractures is formed, is in many respects different from the original cartilaginous mould of the bone, and that in fact true 
bone is developed, in many parts of the body, without the existence of any previous cartilaginous basis. Vide Miescher. Diss, de Os. Genes. Struc, et Yit. 
Berol. 1836; Gerber's General and Minute Anatomy, Lond. 1812; and Carpenter's Human Physiology, 1812.— J. 1'. 



fibres or vessels, have no internal cavity or medullary tissue ; they are solid and homogeneous in their whole extent, but possess 
the outward form of bone, and are invested by a fibrous envelope analogous to that of bone, (perichondrium.) There is another 
peculiarity wbich deserves notice : all those parts of the cartilage which are intended to be replaced by flat bones, viz. of the skull, 
face, and pelvis, represent a continuous layer, without any perceptible boundary or distinction, and the fibrous envelope passes 
uninterruptedly over the entire surface; but the femur, tibia, clavicle, and humerus are quite distinct and accurately defined : the 
latter, it will be recollected, are ultimately to be connected by ligaments, and contribute to form the movable articulations; the 
former still continue to be united by cartilage. About the eighth week, the cartilage, which for a certain time, more or less in 
different instances, occupies the place and performs the functions of bone, becomes hollowed into irregular cavities, and shortly 
afterwards into canals lined by vascular membranes, and filled by a mucilaginous or viscid fluid; at this period a red dot appears 
at some particular point, and ossification immediately commences. The spot first ossified {punctum ossijiculionis) is always 
situated within the substance of the cartilage, never at its surface. Bichat was of opinion that the vessels were not developed at 
this period; that they existed before, but circulated only white fluids, and then, for the first time, began to admit red globules; 
but, be that as it may, the change is marked by the admission of blood into the interior of the cartilage, and the deposition of 
calcareous matter, both appearing to be coincident. The cartilage appears red and injected, where it is in close contact with the 
ossified points ; more externally it is somewhat opaque, and marked by grooves or canals ; in the next remove it retains Us 
original character, presenting, however, in a few points, some vascular canals directed towards the centre of ossification. As the 
process proceeds, the osseous point increases, as well by additions externally, as by interstitial depositions; whilst the cartilage, as 
it becomes excavated by canals and cavities lined by vascular lamelloe, diminishes gradually as the bone increases, and finally 
disappears, being as it were supplanted. 

This is to be considered as the general outline of the process of ossification. The time of its commencement and completion 
varies considerably in different parts of the skeleton. Tbe bones first formed are tbose which enclose the central organs of circula- 
tion, and of the nervous system, the vertebras and ribs being developed very early. The long bones, viz. clavicle, femur, and 
tibia,* present along the centre of their shaft a broad ring of bone at the earliest moment at which their outline can be traced, 
constituting an exception to the general principle, that bone is deposited in the first instance in a bed of cartilage. The jaw-bones 
and clavicle are also ossified at a very early period ; the sternum, pelvis, and extremities being later, which corresponds with the 
order of their appearance and the date of their growth in the animal scries. From the class of fishes, upwards, inaxiilse are 
developed so rapidly as to be completed very early; so are the clavicles when they exist; whilst the sternum, pelvis, and limbs 
grow tardily, and in many instances remain in a comparatively rudimentary state through life. 

In reasoning on the phenomena of ossification, too much has been attributed to the periosteum : its importance and utility 
cannot be questioned, when we consider how frequently partial exfoliations, or even total necrosis of bones, follow as a conse- 
quence of injuries of their fibrous investment. Some persons have, however, gone farther than this, and have even contended 
that it is the periosteum which produces bone, as if the fibrous membrane acted as its secreting organ ; but it may be said that it 
is its vessels which secrete, and not the membrane. The vessels, however, belong to the bone, not to the periosteum ; and more- 
over, in many parts, the first ossific deposits take place in the centre of cartilage, and therefore at a distance from that membrane. 

THE SKELETON. 

The osseous structure is peculiarly fitted, by its solidity and hardness, not only to give support to the soft parts, but also to 
furnish points of attachment to the muscles, by which the different movements are excited. This solid frame-work of the body 
is made up of a number of separate pieces, the aggregate of which has been termed " the skeleton" (scclctum, nxi%\u, to dry.) 
The vertebral column may be considered as the central or fundamental part of the whole, both because it exists in all animals 
which possess an internal osseous skeleton, and also be.cause the different parts of the osseous system are either immediately or 
mediately connected with it as a common centre. Thus, on its superior extremity or apex it supports the skull ; laterally it gives 
attachment to the ribs, which arch forwards, to form, with the sternum, a bony case for the lodgment of the organs of respiration 
and circulation, at the same time that they furnish externally points of support for the superior extremities: inferiorly the column 
is immovably connected with the pelvic bones, which are articulated with those of the lower extremity. 

When proceeding with the description of the human body, it is usual to consider it as divisible into head, trunk, and extre- 
mities, which is sufficient for the purposes of a regional division ; but the skeleton must be viewed in a different way, particularly 

PLATE III. 

Skeleton of an adult female, after Cheselden. This author, in his description of the plate, observes that it presents " the snme propor- 
tions as the Venus de Medicis." 

* Howship, Med. Chir. Transactions. 



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if reference is made to its conformation in the various orders of animals— to its developement — and to the subordination of its 
component parts. The spine being its essential constituent, all the others (viz. the ribs and sternum, clavicle, scapula, and upper 
extremities, the pelvic bones and lower extremities) rank as accessories. The sacrum and coccyx are obviously parts of the spine, 
so likewise are the cranial bones; for, though in outward appearance they differ so much in man and the higher animals from 
the bones of the spine which are placed beneath them, and with which they are articulated, they still are but modifications of 
similar organic elements — repetitions, in fact, of like parts differently developed to suit the peculiar relations into which they enter, 
and the purposes which they are designed to serve. 

The number of pieces which compose the osseous system varies in the different ages of life ; for some, which in the first 
instance are divided into two or more portions, become soldered together as the process of ossification goes on. But authors are 
far from being unanimous as to the number of bones which they recognise even in the adult. Do the sesamoid bones form part 
of the skeleton, or are they mere accessory structures developed in tendons ? Are the teeth, os hyoides, and ossicula auditus, to 
be enumerated as components or accessories ? Monro and Soemmering reckon 260 bones ; and Meckel, who takes the number 
at 253, includes the teeth, patellae, ossa sesamoidea, os hyoides as five pieces, sternum as three, coccyx as four, and the small 
bones of the ear. If, however, we omit those just named, as being either accessories or connected with special organs, the whole 
number of pieces found in the ordinary skeleton will be 197, as follow : — 

The spinal column, properly so called, consists of 24 vertebra?, the sacrum and the coccyx, (26.) 
. The skull is made up of eight cranial bones, viz. the occipital, two parietal, two temporal, the frontal, the ethmoid and sphenoid : 

• PLATE IV. 

The bones of the vertebral column articulated. 

Fie. 1. The vertebral column seen from the front. 

No. 1. The atlas ; the number is placed on the anterior arch of this bone. 2, 2. Its superior articular processes. 3, 3. Its inferior arti- 
cular processes. 4, 4. Its transverse processes. 5. The axis. 6. The base of the odontoid process. 7, 7. The transverse pro- 
4 cesses, remarkable for their small size as compared with those of the atlas. 8. The body of the third cervical vertebra. 9. The bodjr 

of the fourth. 10. The body of the fifth cervical vertebra. 11. The sixth cervical vertebra. 12. The seventh cervical vertebra. 
13. The anterior tubercles of the transverse processes of the cervical vertebrae. 14. Their posterior tubercles. 15. The body of 
the first dorsal vertebra. 16. The body of the sixth. 17, 18. The bodies of the eleventh and twelfth dorsal vertebrae. 19, 19. 
The transverse processes of the dorsal vertebra;. 20, 20. Articular surfaces upon the extremity of the tranverse processes. These 
surfaces are formed on all the transverse processes with the exception of the two last. 21, 21. The transverse processes of the 
two last dorsal vertebrae, which are remarkable for their small size. 22. The body of the first lumbar vertebra. 23. The last 
lumbar vertebra. 24, 24. The transverse processes of the lumbar vertebrae, which are long and sharp. 25. The intervertebral 
substances of the lumbar vertebrae ; the same substance is seen between the other vertebrae composing the column. 26, 26. The 
sacrum. 27, 27. The transverse lines on the sacrum, marking its original conformation of separate pieces. 28, 28. The anterior 
sacral foramina of one side ; the same foramina are seen on the opposite side. 29. The promontory of the sacrum. 30. The first 
piece of the coccyx, anchylosed to the extremity of the sacrum, and forming a fifth pair of sacral foramina, 31. 32. The lower 
portion of the coccyx, consisting of three pieces and a rudiment of a fourth. 

Fig. 2. A side view of the vertebral column, showing its curves. 

No. 1. The atlas. 2. The posterior arch of the atlas. 3. The groove upon which the vertebral artery rests. 4. The axis. 5. The 
spinous process of the axis, remarkable for its great size. 6. The seventh and last cervical vertebra. 7. The long spinous process of 
the seventh cervical vertebra. 8, 8. The laminae of the cervical vertebrae. 9, 9. Their transverse processes. 10. The foramen 
for the vertebral artery in the transverse process of the axis. 11. The body of the first dorsal vertebra. 12. The body of the sixth 
dorsal vertebra. 13. The body of the twelfth. 14, 14. The transverse processes of the dorsal vertebra, upon which the articular 
depression for the tubercles of the ribs is seen. 15, 15. The spinous processes of the dorsal vertebrae. 16. The interver- 
tebral foramina in the dorsal region- of the spine. 17, 17. The intervertebral substances in the dorsal region. 18. Depression 
upon the side of the body of the first dorsal vertebra, for the first rib. 19, 19. Depressions upon the sides of the bodies of the 
vertebrae for other ribs. 20. The first lumbar vertebra. 21 The fifth or last lumbar vertebra. 22, 22. The intervertebral sub- 
stances connecting the bodies of the lumbar vertebrae. 23, 23. Intervertebral foramina in the lumbar region. 24, 24. The trans- 
verse processes of the lumbar vertebrae. 25, 25. Articular processes of the lumbar vertebrae. 26, 26. Spinous processes of the lum- 
bar vertebrae. 27. The rudimentary spinous processes of the sacrum. 28. The surface of the sacrum, which articulates with the 
ilium. 29. The rough portion of the sacro-iliac articulation which gives attachment to the posterior sacro-iliac ligaments. 30. The 
four pieces of the coccyx. 

Fig. 3. Posterior view of the vertebral column. 

No. 1. The atlas. 2. The odontoid process of the axis seen articulating with the anterior arch of the atlas. 3, 3. Transverse processes 
of the atlas. 4. The axis. 5. The seventh cervical vertebra. 6,6. The bifid spinous processes of the cervical vertebrae. 7. The 
first dorsal vertebra. 8. The last dorsal vertebra. 9,9. The articulating processes of the dorsal vertebrae. 10, 10. The short 
transverse processes of the eleventh and twelfth dorsal vertebrae. 11. The first lumbar vertebra. 12. The fifth lumbar vertebra. 
13,13. The articular processes of the lumbar vertebras. 14,14. The sacrum. 15,15. Its radimentary spinous processes. 16,16. 
The posterior sacral foramina. 17. The commencement of the sacral canal. 18. The termination of the sacral canal. 19, 19. 
The articular borders of the sacrum. 20. The coccyx. 
Bones. — 2 



10 

and of fourteen facial, viz. two nasal, two lachrymal, two superior maxillary, two malar, two palatal, two turbinated, one vomer, 
and the inferior maxillary bone, (22.) 

The ribs are 24 in number, (twelve on each side,) with the sternum, (25.) 

The two superior extremities consist each of a clavicle and scapula, humerus, radius, and ulna, eight carpal bones, five meta- 
carpal, and fourteen in the digital rows, (64.) 

The two inferior extremities comprise, each, one pelvic bone, (innominatum,) one femur, tibia, and fibula, seven tarsal bones, 
five metatarsal, and fourteen digital, (60.) 

In the skeleton we recognise two great cavities, (which are again variously subdivided ;) one anterior and inferior, compris- 
ing the thorax and abdomen ; the other posterior and superior, formed by the union of the vertebral canal with the cranial cavity. 

Vertebral column. — The vertebral column (columna vertebralis, rachis, spina) is situated along the median line, at the pos- 
terior part of the trunk, the length of which it determines. Anteriorly it presents the form of an irregular pyramid — posteriorly, 
a series of elongated processes, (spina?,) disposed regularly one beneath the other, from which circumstance the term " spine" is 
derived. Viewed as a whole, it resembles at first sight the shape of a long bone, but it is very differently constructed. As it 
receives the weight of the head and trunk, and transmits it to the base on which its rests, it requires to be firm and resisting, its 
power of resistance increasing gradually from above downwards. Being the centre of all the movements of the body, it must 
be as pliant and flexible as a bow, but yet firm, in order to give adequate protection to the spinal cord which it encloses. All 
these conditions are attairjed by its being made up of several small pieces united by an elastic substance, the motion permitted 
between each pair being slight, while the aggregate of all is considerable. 

The vertebrae, or separate pieces of which the column is made up, are so named from their mobility, (vertere, to turn.) They 
are divided into true and false ; the former term being applied to those which remain separate in the adult, and retain their mo- 
bility — the latter to such as become united into one mass, (viz., the sacrum,) or degenerate, as it were, and lose all the ordinary 
characters of vertebras, (viz., the coccyx.) The size of the vertebra? increases from above downwards as far as the first pieces 
of the sacrum, from which it diminishes towards the end of the coccyx, where it terminates by a point ; so that the column may 
be said to consist of two pyramids applied to one another at their bases. The superior, or moveable one, however, does not 
taper regularly from above downwards in its entire length ; it becomes somewhat narrowed and constricted as it were at the 
third dorsal vertebra, after which it gradually enlarges towards its base. 

PLATE V. 

The vertebrae of the three regions of the spine, with separate vertebrae from the cervical region ; after Cheselden. 

Fig. 1. A front view of the seven cervical vertebrae articulated. 

No. 1. The atlas. 2. The axis. 3. The seventh and last cervical vertebra. 

Fig. 2. An atlas seen upon its upper surface. 

No. 1. The anterior arch of the atlas. 2. Its anterior tubercle. 3 The posterior arch. 4. The posterior tubercle, or rudimentary 

spinous process. 5, 5. The intervertebral notch, which supports the vertebral artery at each side. 6, C. The transverse processes. 

7, 7. The foramen for the transmission of the vertebral artery. 8, 8. The superior articular surfaces of the atlas. 9, 9. The 

tubercles to which the extremities of the transverse ligament are attached. 
Fig. 3. The atlas seen from below. 
The references to the preceding figure are equally applicable to this: the additional points exhibited in the present view are, 10. The 

articular surface for the odontoid process of the axis, on the posterior part of the anterior arch. 11,11. The inferior articular sur- 
faces, which are flat and nearly horizontal. 
Fig. 4. A lateral view of the axis. 
No. 1. The body of the axis. 2. The odontoid process of the axis. 3. The smooth articular surface corresponding with the posterior 

aspect of the anterior arch of the atlas. 4, 4. The lamin*. 5. The spinous process. 6. The transverse procesl 7. The foramen 

for the vertebral artery. 8. One of the superior articular processes. 9. One of the inferior articular processes. 
Fig. 5. One of the middle cervical vertebras, seen upon its upper surface. 
No. 1. The body. 2, 2. The transverse processes. 3, 3. The anterior tubercles of the transverse processes. 4, 4. The posterior 

tubercles. 5, 5. Foramina for the vertebral arteries. 6, 6. The pedicles, rendered concave by the intervertebral notches. 7, 7. 

Superior articular processes. 8. The outer surface of one of the inferior articular processes. 9, 9. Lamin* of the vertebra lo! 

The spinous process. 1 1 . The bifid termination of the spinous process. 12. The ring of the vertebra for the location of the spinal 

cord with its membranes. 
Fig. 6. A cervical vertebra seen upon its under surface. 
No. 1. The anterior surface of the body. 2. Its under surface. 3, 3. Transverse processes. 4, 4. The inferior articular processes. 

5. The spinous process. 6. Its bifid extremity. 7, 7. The pedicles of the laminae. 
Fig. 7. The seventh cervical vertebra, or vertebra prominens, seen upon its upper surface. 
No. 1. The upper and concave surface of the body of the vertebra. 2. Its posterior surface, upon which foramina are seen for the veins 

of the vertebra. 3, 3. Transverse processes. 4, 4. The pedicles of the laminae. 5, 5. The laminae. C, 6. The superior articular 

processes. 7. The long spinous process. 
Fig. 8. A lateral view of the twelve dorsal vertebrae. 
Fig. 9. The five lumbar vertebra?. The vertebra in the three figures, 1, 8, and 9, constitute together the same vertebral column. 



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Vertebrae, division of. — The true vertebrae are divided into three sets, named from the regions which they occupy, cervical, 
dorsal, lumbar. The sacrum and coccyx, which form the remaining part of the column, shall be described with the bones of the 
pelvis, as they enter into the composition of that cavity, and maintain important relations with the organs which it contains. 

The true vertebrae present, 1, certain general characters by which they may at once be distinguished from bones of any other 
class ; 2, those of each region, (cervical, dorsal, lumbar,) exhibit peculiar characters by which they are severally distinguished. 

General characters of a vertebra. — It is usual to say that a vertebra consists of body and processes — the body being the 
primary or fundamental part. The objects presented by each of these bones are, a body, a ring, articulating processes, transverse 
and spinous processes, and notches : of these, the ring, or foramen, merely to suit the purposes of methodical description, may be 
considered the central part. As the whole series of vertebrae is intended to form a pillar of support, each, with the exception of 
the first, presents in front a convex mass, (the body,) which is a section of a cylinder, and which, by being piled one over the 
other, form the pillar. As each bone must be securely joined with the one above it, and that below it, there exist certain promi- 
nences for articulation with them. The column being flexible, and partaking in the several movements of the body, it is required 
that there be levers for the attachment of the muscles or moving powers. Finally, it is necessary that a free communication 
should be allowed for the nerves with the nervous centre contained in the canal. 

The ring (foramen vertebrale, rachidium) is formed in front by the body, and posteriorly by what is named the arch of the 
vertebra, from which latter the several processes project. As the vertebrae are piled one over the other, the rings are arranged 
so as to form, with the aid of the interposed ligamentous structures, a flexible canal for the lodgment and protection of the spinal 
cord. 

The body forms the anterior and most considerable part of the bone. Rounded before, and marked in the middle by a 
transverse groove, which gives it a constricted appearance, it is slightly hollowed posteriorly, where it contributes to the formation 
of the vertebral canal, and in most instances is flat on the superior and inferior surfaces, by which, through the medium of a layer 
of fibro-cartilage, it is connected with the contiguous bones. Its outer surface all round presents numerous foramina for the pas- 
sage of nutritious vessels. From the body, at its lateral margins, two processes pass backwards called " pedicles." The pedicles 
join with the lamellae, or plates; and these, by inclining inward, meet at the median line posteriorly, so as to complete the "arch" 
of the vertebra. From the point of junction of the pedicles with the lamellae at each side, the articulating and transverse processes 
project, and from the union of the two lamellae the spinous processes take their origin. 

Articulating processes. — For maintaining the connexion between the contiguous vertebrae, there are four processes, — two 
superior, and two inferior, — which project, one on each side, from the junction of the lamella with the pedicle. Two of these 
processes project upwards, and two downwards; the smooth surfaces of the upper pair look backwards, those of the lower, 
forwards ; they are coated with cartilage, and articulate with corresponding processes of the next vertebrae. Their margins are 
rough for the attachment of ligaments. 

The transverse and spinous processes form a series of levers for the attachment of muscles. The transverse processes, two 
in number, (one on each side,) and named from their direction, project laterally from the arch near the articulating processes, 
between which their bases are interposed. The spinous process is a single projection, situated posteriorly in the median line ; this 
process, or rather the appearance presented by the aggregation of those of the several vertebrae, has given to the entire column one 
of its designations, (spine.) The parts of the arch' which intervene between the bases of the spinous and the transverse processes 
are named laminae or plates. Lastly, the processes which extend from the lamellae to the body of the bone, are called " pedicles," 
as above stated. In each pedicle are seen two excavations, or notches, (incisurae,) one on the upper, the other on the lower 
border, the latter being deeper than the former. When the vertebrae are placed in their natural position, the notches in the con- 
tiguous margins of each pair of them form rounded apertures, which communicate with the vertebral canal, and give transmission 
to the spinal nerves and to the entering and emerging vessels. From their position and mode of formation they are called the 
inter-vertebral foramina, (trous de conjugaison.) 

These remarks apply generally to all the vertebrae ; but as each class presents peculiar characters which distinguish those 
included within it from others, and as there are peculiarities which mark certain individuals of each class, it becomes necessary to 
examine them more in detail. 

The cervical vertebrae are seven in number ; they are smaller than those in the other regions, which results from the size of 
the body and processes being less than that of the corresponding parts in the dorsal and lumbar class. The vertebral foramen is 
of a triangular form, and larger proportionally than in the other classes. The body, elongated transversely, is thicker anteriorly 
than posteriorly; for the under and fore part of each dips down a little. The upper surface is broader than the under one, and is 
rendered concave from side to side, by two little plates, which project upwards from its margins. The lower surface is slightly 
convex, and rounded off at the sides. The superior articular processes are flat and oblique in their direction, so as to look back- 
wards and upwards, whilst the inferior incline downwards and forwards. The transverse processes, short, and bifid at their 
extremities, present a groove superiorly for the transmission of the nerves, and at their base a foramen, through which in most of 
them the vertebral artery passes. It will be observed, that these processes have two roots or points of connexion with the 
tebra. The posterior one springs from the junction of the pedicle with the arch, and therein corresponds with the trans' 



processes in the back and loins. The anterior one is attached to the side of the body of the vertebra, and ranges with the ribs, 
of which it is a rudiment. The formation of the foramen can, from these facts, be readily indicated. The osseous points, which 
here represent the ribs, not being required for any special purpose, remain in their rudimentary condition, and merely incline back- 
wards, so as to become anchylosed with the true transverse processes which lie behind them. They thus enclose a space, viz., 
the foramen, which, however, cannot be said to be intended to lodge the vertebral vessels, as it exists in the seventh cervical ver- 
tebra, through which they do not pass, and in the sixth and fifth in those cases in which the artery enters at the fourth. The 
spinous process is short, projects horizontally backwards, and is bifid at its extremity. The plates are narrower and longer than 
in the other regions. The notches are deeper and larger in the upper than in the lower border of the pedicles, in all except the 
second. They lie behind the articular processes in the first, but before them in the rest. 

The dorsal vertebrae, twelve in number, are intermediate in size, as well as in situation, between the cervical and the lumbar. 
The foramen is smaller than in the cervical or lumbar region, and is nearly circular in its form. The lateral notches, and conse- 
quently the inter-vertebral foramina which they form, are larger than those in the neck ; and those at the lower margin of the 
pedicles are much larger and deeper than those on the upper. The depth of the body, taken from before backwards, is greater 
than its breadth from side to side ; it is convex and prominent on the anterior surface, flat and plain at the upper and lower ; at 
each side of the body may be observed a slight notch, in the superior as well as in the inferior border, — these, when the vertebra 
is placed in apposition with the adjacent ones, form oval depressions for the reception of the heads of the corresponding ribs. The 
articulating processes are nearly vertical in their direction ; the superior looking backwards, the inferior forwards. The transverse 
processes arc long and inclined backwards, and on the anterior surface of each of their tubercular terminations is situated a slight 
excavation, which, in the fresh state, is tipped with cartilage, and articulates with the tubercle of the rib. The spinous processes, 
elongated and triangular, are directed downwards, and terminate in a tubercle. The plates are broad and thick, but shorter than 
those in the neck. 

The lumbar vertebrae, five in number, are larger than either of the other sets. The foramen of each vertebra in this region 

PLATE VI. 

Section of the vertebral column, showing the texture of the divided surfaces, and the direction of the vertebral canal ; with views of the 
dorsal and lumbar vertebras : after Cheselden. 

Fio. 1. The sixteen superior vertebrae. 

No. 1. The atlas. 2. The axis. 3. The seventh cervical vertebra, or vertebra prominens. 4. The first dorsal vertebra. 5. The ninth 
dorsal vertebra. 6. The most projecting of the spinous processes of the cervical vertebras, belonging to the vertebra prominens. 
7, 7. The oblique direction and imbricated position of the spinous processes of the dorsal vertebras is here shown. 8, 8. The inter- 
vertebral foramina, formed by the approximation of the intervertebral notches. 9, 9. The vertebral canal. 

Fig. 2. The eight inferior vertebras of the spinal column, with the sacrum. 

No. 1. The tenth dorsal vertebra. 2. The last dorsal vertebra. 3. The first lumbar vertebra. 4. The last lumbar vertebra. 5 5. The 
short and nearly horizontal spinous processes of the last dorsal vertebras. 6, 6. The broad spinous processes of the lumbar vertebrae. 

7, 7. The intervertebral foramina. 8, 8. The vertebral canal. 9, 9. The sacrum. 10. A part of its anterior surface, upon which 
two of the anterior sacral foramina, 11, 11, are seen. 12, 12. Fissures in the body of the sacrum, marking its original construction 
of four pieces. 13. Section of the rudimentary spinous processes of the sacrum. 14, 14. The sacral canal, in which several 
of the posterior sacral foramina, 15, 15, are seen. 16. The termination of the sacral canal. 17. The coccyx, consisting of four 
pieces. 

Fig. 3. A dorsal vertebra seen upon its under surface. 

No. 1. The anterior surface of its body. 2. The under surface. 3, 3. Transverse processes. 4, 4. The inferior articular process. 
5. One of the superior articular processes. 6, 6. Lamina: of the vertebra. 7. The vertebral ring. 8. The spinous process! 
9. Its tubercle. 

Fig. 4. A dorsal vertebra seen from above. 

No. 1. The superior surface of the body. 2. Its lateral surface. 3. Part of its posterior surface. 4, 4. The transverse processes. 
5, 5. Superior articular processes. 6, 0. Posterior surface of the laminae. 7. The spinous process, directed downwards and termi- 
nated inferiorly by the tubercle. 

Fig. 5. The last dorsal vertebra, approaching in appearance to the characters of the lumbar vertebras. 

No. 1. Its body. 2. The depression on the side of the body for the articulation of the last rib. 3, 3. The superior articular processes 
4. One of the inferior articular processes. 5. The pedicle. 6. The superior intervertebral notch. 7. The inferior intervertebral 
notch. 8, 8. The transverse process of the vertebra. 9. Its spinous process. 

Fig. 6. One of the lumbar vertebras turned upwards so as to show its under surface. 

No. 1. Its body. 2. One of its pedicles. 3, 3. The transverse processes. 4. One of the superior articular processes. 5, 5. The inferior 
articular processes. C. The spinous process. 7. The vertebral ring. 8. The under surface of the body. 

Fig. 7. One of the lumbar vertebras seen from above and behind. 

No. 1. The upper surface of the body of the vertebra. 2. Its posterior surface, on which openings for the transmission of several large 
veins are seen. 3. The pedicle of one of the laminae, immediately above which the superior intervertebral notch is seen. 4, 4. Trans- 
verse processes. 5, 5. The superior articular processes. 6. One of the inferior articular processes. 7, 7. Laminas of the vertebra. 

8. The spinous process. 



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13 

is large and triangular. The notches for the formation of the intervertebral foramina are very deep, especially the inferior pair. 
The body, broader from side to side than from before backwards, is flat on its superior and inferior surfaces. It is not so convex 
anteriorly as that of the dorsal vertebrae. The articulating processes are thick, strong, and disposed vertically ; the superior pair, 
concave, look inwards and backwards; the inferior, convex, outwards and forwards; the former are farther apart than the latter, 
hence they receive and in a manner embrace the lower articulating processes of the vertebra above them. The transverse pro- 
cesses, long, thin, and horizontal, do not project backwards like those of the dorsal vertebrae. The spinous process is broad, flat, 
and nearly of a square form, so that it terminates not by a pointed extremity, like those in the dorsal region, but presents rather a 
compressed and rough border. The plates, though shorter, are deeper and thicker than those of the dorsal vertebrae. 

The general characters of the vertebrae, and the differences which characterize those of different regions, being considered, it 
remains to point out certain peculiarities presented by some individual bones in each set. It may be here stated generally, that 
the vertebrae situated at the extremities of each region assimilate in some degree to the characters of those in whose vicinity they 
are placed. Thus, for instance, the lower pieces of the cervical region begin to resemble the dorsal vertebrae, and the latter 
become, by a similar transition, assimilated to the lumbar, — the characters peculiar to each region being best displayed by the bones 
situated towards its middle point. 

Peculiarities of certain vertebras. — The first, second and seventh cervical vertebrae present some characters which distinguish 
them from the others. 

The first, or atlas, (so called from supporting the head,) is an irregular ring of bone, which presents nothing analogous either 
to the bodies or spines of the other vertebrae. The ring, in the fresh state, is divided into two parts, by a transverse ligament, — 
the anterior one being occupied by the odontoid process of the axis, the posterior by the spinal cord, — it presents in front a small 
arch of bone, the anterior surface of which is marked by a tubercle ; the posterior by a smooth depression, adapted to the odontoid 
process of the axis. The posterior segment of the ring is considerably larger than the anterior ; at its middle point it presents a 
tubercle, which is the analogue of the spinous processes ; it is thick and round in the greater part of its extent ; but at its junction 
with the rest of the vertebra there exists on the upper border at each side a smooth groove, which lies behind the superior articular 
process, and marks the tortuous course pursued by the vertebral artery previously to entering the cranium. This groove is ana- 
logous to the notches in the other vertebras, for it transmits the first spinal nerve as well as the vertebral artery ; it is sometimes 
converted into a foramen by a spicula of bone. — The articulating surfaces are horizontal and large ; the superior pair receive the 
condyles of the occipital bone ; they converge in some sort towards the forepart of the bone ; and as their form is oval, and their 
surface concave from before backwards, they look towards one another; at the inner margin of each is a rough surface, which 
gives attachment to the transverse ligament. The inferior pair, on the contrary, are flat, and nearly circular in their form. The 
parts of the vertebra (lateral masses) on which these processes are situated are of very considerable thickness, because the weight 
of the head, which in others is received by the bodies, rests here on the articular surfaces. The transverse processes project 
considerably on each side, and terminate in a rounded point ; at the root of each is situated the foramen, which transmits the 
vertebral artery. 

The second vertebra, or axis, (so called from forming the pivot on which the head rotates,) is somewhat triangular in its form. 
The body presents anteriorly a vertical ridge, bounded on each side by a depression for the attachment of the longus colli muscle ; 
superiorly it is surmounted by a process, (odontoid, p. denlatus; whence is derived the name vertebra dentata,) presenting two 
smooth surfaces, one for its articulation with the atlas, the other with the transverse ligament which retains it in its situation ; 
being constricted inferiorly, and somewhat enlarged towards the summit, these parts of the process are called respectively its neck 
and head. The superior articulating processes are of considerable size, and nearly horizontal ; they are close to the body, so as to 
communicate to it the weight of the head, transmitted to them by the articular processes of the atlas; the inferior pair are oblique, 
and of the same size as in the vertebrae beneath them. The transverse processes are neither grooved nor bifurcated, and the 
foramen at their root is inclined obliquely outwards. The spinous process is very large, and gives attachment to several muscles; 
it is deeply grooved on its inferior surface ; the plates which support it are of proportionate size. 

The seventh, or prominent vertebra, approaches in its characters to those of the dorsal region ; its spinous process terminates 
in a tubercle, and is so long as to be, in the natural condition, felt underneath the skin, whilst the other cervical spines lie more 
deeply, and are covered by muscles ; hence the term " prominent," so commonly applied to this vertebra. The transverse pro- 
cess, though pierced by a foramen, presents but a slight appearance of a groove on its upper surface, and seldom more than a 
trace of a bifurcation at its extremity. 

The first dorsal vertebra is marked at each side by a complete articular surface for the first rib, and on its inferior border 
by a slight excavation, which receives half the head of the second : the upper articular processes are oblique, and the spinous 
more nearly horizontal than those below it. 

The tenth dorsal vertebra is usually marked by an articular surface, which receives the entire of the head of the corresponding rib. 

The eleventh is distinguished by its transverse processes not presenting an articulating surface for the tubercle of the rib, 
whilst the form of its spinous process, of its lamellae and body, approaches that of the lumbar vertebrae. 

The ttvelfth dorsal vertebra resembles the eleventh in most of its characters ; but its transverse processes are shorter, and the 



14 

lower articular pair convex and directed outwards, so that its conformation resembles that of the lumbar vertebra in these 
particulars. . 

Amongst the lumbar vertebra?, the fifth only is distinguishable by any peculiarity deserving of notice, its body being thicker 
anteriorly than posteriorly, and its transverse process short, thick, and rounded. 

The bones just described, when ranged in their natural position, form a pyramid, die length of which is equal to about two 
feet two or three inches ; taken as a whole it presents an anterior and posterior surface, two lateral surfaces, a base, and a summit, 
each deserving a particular notice. 

The anterior surface is broad in the cervical, narrow in the dorsal, and again expanded in the lumbar region ; it is marked 
by a series of transverse grooves corresponding with the centre of the bodies of the vertebrae, and in the fresh state is covered by 
the anterior common ligament. When viewed in profile, it presents three curves depending on the different degrees of thickness of 
the anterior and posterior part of the bodies of the vertebras in the different regions, but still more on that of the intervertebral sub- 
stance. In the neck and loins the convexity of the curve is forwards ; in the back it is in the opposite direction. A slight degree 
of lateral curvature is also observable in most cases in the dorsal region, the convexity of which is directed towards the right side. 
The older anatomists imagined this to be produced by the action of the aorta beating against the left side of the column ; but 
Bichat attributed it to the effect of muscular action, and explained it in the following way : — As most persons are disposed to use 
the right arm in preference to the left, the muscles of that side become stronger, and act with more power on the points to which 
they are attached ; when making efforts, as in pulling, the body is curved to the left, which gives an additional advantage to the 
muscles ; and the habitual use of this position gives rise to some degree of permanent curvature. In support of this explanation 
of the fact, Beclard has stated that he found in one or two individuals, who were known to have been left-handed, the con- 
vexity of the lateral curve directed to the left side. 

The posterior surface presents along the median line the spinous processes, varying in form and direction, as has been 

PLATE VII. 

The ligaments of the vertebral column, and of the costo-vertebral and costo-sternal articulations. 

Fig. 1. The ligaments situated upon the anterior aspect of the vertebral column, in the dorsal region. 

Nos. 1, 1. The anterior common ligament. 2,2. The intervertebral substances. 3, 3. The anterior costo-vertebral or stellate liga- 
ments. 4, 4. The anterior costo-transverse ligaments. 

Fig. 2. The ligaments of the posterior aspect of the vertebral column. 

Nos. 1,1. The supra-spinous ligaments. 2,2. The ligamenta subflava. 3,3. The posterior costo-transverse ligaments, 4,4. The 
antrrior costo-transverse ligaments. 

Fig. 3. A posterior view of the bodies of three of the dorsal vertebrae. 

Nos. 1, 1. The cut surfaces of the pedicles of the vertebrae. 2,2. The posterior common ligament. 3,3. The intervertebral sub- 
stances. 4", 4. Foramina for the transmission of the venae basis vertebrae. 

Fig. 4. Arches of three of the dorsal vertebrae. 

Nos. 1,1. The cut surfaces of the pedicles. 2. Superior articular processes of the uppermost of the three. 3, 3. Transverse pro- 
cesses. 4, 4. Ligamenta subflava. 

Fig. 5. The intervertebral substance between two vertebrae, showing its composition of oblique fasciculi of fibres. 

Fig. 6. The surface of a section of the intervertebral substance. 

Nos. 1, 1. Concentric circles of fibrous structure. 2. The pulpy fibro-cartilaginous tissue of the centre of the intervertebral substance. 

FrG. 7. A lateral view of the ligaments of the vertebral column, with those of the costo-vertebral articulation. 

Nos. 1, 1. The anterior common ligament. 2,2. The intervertebral substances. 3,3. The anterior costo-vertebral or stellate liga- 
ments ; the numbers are placed on the middle fasciculi. 4. The superior fasciculus of the stellate ligament. 5. Its inferior fasci- 
culus. 6,6. The anterior costo-transverse ligaments. 7. The articular facets of two adjoining vertebrae, serving for the articulation 
of a single rib. The numeral is placed upon the intervertebral substance, which serves for the attachment of the interarticular 
ligament. 8. The articular surface at the extremity of the transverse process, for the attachment of the same rib. 9. The supra- 
spinous ligaments. 10. One of the inter-spinous ligaments. 

Fig. 8. A vertebra, with its articulated ribs, seen from above, in order to show the middle costo-transverse ligament. 

No. 1. The surface of the body of the vertebra, coated with intervertebral substance. 2, 2. The ribs divided through their middle. 
3, 3. The middle costo-transverse ligaments. 4, 4. The posterior costo-transverse ligaments. On the left side, at 5, the articulation 
of the tubercle of the rib with the transverse process is partly laid open. 

Fig. 9. Section of a vertebra with the head of a rib, through the costo-vertebral articulation. 

No. 1. Part of the anterior common ligament. 2. The intervertebral substance. 3, 3. The two synovial cavities of the costo-vertebral 

articulation, separated by 4, the interarticular ligament. 
Fig. 10. The costo-sternal articulation seen from the front. 

Nos. 1, 1. Cartilages of the ribs. 2,2. Anterior costo-sternal ligaments. 3, 3. Articular surfaces of the sternum, for the costal 

cartilages of the opposite side. 
Fig. 11. The costo-sternal articulation, seen from behind. 
Nos. 1, 1. Costal cartilages. 2, 2. Posterior costo-sternal ligaments. 3, 3. Longitudinal tendinous fibres on the posterior surface of 

the sternum. 4, 4. Articular surfaces of the opposite border of the sternum. 



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already stated ; being horizontal in the cervical and lumbar regions, and nearly vertical in the dorsal. Those in the cervical and 
dorsal regions correspond pretty exactly with the middle line, but in the back the spines will be observed in many instances to 
incline, some to one side, some to the other. On each side of these are the vertebral grooves, extending from the base of the 
skull to the sacrum ; their breadth corresponds with that of the lamina? ; they are broad but shallow in the neck, and become 
deep and narrow lower down. Along the grooves are seen the spaces between the laminae, which in the natural condition are 
filled up by the yellow ligaments. The breadth of these intervals is very trifling in the neck and in the greater part of the back ; 
it increases in the lower third of the dorsal, and still more in the lumbar region. The interval between the occipital bone and the 
atlas is considerable, and so is that between the last lumbar vertebra and the sacrum. 

The lateral surfaces of the column present the transverse processes, varying in form and character in the different regions : 
before these are situated the intervertebral foramina, and more anteriorly still, in the dorsal region, the articulating surfaces 
which receive the heads of the ribs. 

The summit is articulated with the occipital bone, and supports the head ; whilst the base, or broader extremity, rests on the 
sacrum. Along the entire extent of the column runs the vertebral canal, which is broad and triangular in the cervical and lum- 
bar regions, circular and contracted in the dorsal. The canal may be said to expand at its upper extremity into the cranial cavity, 
and at its lower end to be prolonged into that of the sacrum. 

Developement. — In the description here given of the vertebrae, each of them is considered as a single bone ; and so it is 
when fully formed. But in the foetal state and in early infancy each consists of at least three pieces, representing so many cen- 
tres of ossification, one corresponding with the body and one for each lateral mass. The spinous process has even been observed 
to commence by a separate point, and analogy would lead to the inference that the anterior and posterior segments of the body 
are produced from distinct centres. Are we to go farther still, and admit that the body in the first instance consists of two lateral 
halves ? If so, instead of three, we should have eight incipient osseous points in each of these bones. The atlas has three osseous 
nodules from which its ring is completed, one at each side for the lateral masses, and one in front for the anterior arch. Bichat 
found in some cases two additional points in the posterior arch. The second vertebra commences by five points at least, two of 
them being in its odontoid process. 

Of the Skull. — The skull is of a spheroidal figure, compressed on the sides, broader behind than before, and supported by 
its base on the vertebral column. It is divided by anatomists into two parts, the cranium and the face ; the former being composed 
of eight bones, viz., the occipital, two parietal the frontal, two temporal, the sphenoid, and the ethmoid ; the latter is made 
up of fourteen bones, viz. two superior maxillary, two malar, two ossa nasi, two ossa palati, two ossa unguis, two inferior 
turbinated bones, the vomer, and inferior maxilla; the frontal bone is so situated as to be common to the cranium and face. 
The bones of the ear are not included in this enumeration, as they belong rather to a special organ than to the skeleton considered 
as the frame-work of the body. 

The Occipital Bone. — The occipital bone (os occipitis) is situated at the posterior part of the base of the skull , broad behind, 
narrowed to a point before, of a trapezoid figure, presenting two surfaces, four borders, and four angles. To place the bone in its 
natural position, hold it so that the great foramen and the articulating processes beside it shall look directly downwards; the thick 
process in front of the foramen will then project forwards into the base of the skull, whilst the broad expanded part behind it 
arches upwards and a little forwards, forming the posterior wall of the cavity. External surface : this is convex in its general 
outline, and presents a little above its centre a rough prominence, the occipital protuberance, the part between which and the 
superior angle is smooth. Extending obliquely outwards at each side from the protuberance is a rough line, called the superior 
curved line, to distinguish it from another which is lower down between it and the great foramen, called the inferior curved line; 
both are prominent, and give attachment to muscles, as also do the rough depressions between them. These are crossed by a 
vertical line, extending forwards from the protuberance to the foramen. 

The occipital foramen, (foramen magnum,) which is of an oval figure, (its long diameter extending from before backwards,) 
gives transmission to the spinal cord, the vertebral arteries, and spinal accessory nerves. 

At each side of the foramen, but nearer its anterior part, are situated the articulating processes, {condyles}) two oblong emi- 
nences, which articulate with the first vertebra. These converge from behind forwards ; their inferior surface, which in the fresh 
state is smooth, covered with cartilage, and convex in its general outline, looks downwards and outwards, and is adapted for 
moving on the concave surface presented by the articulating processes of the atlas. The inner border of each condyle is rough, 
and receives the insertion of the check ligaments, which extend up from the odontoid process of the axis ; the outer border, 
depressed and not so well marked, gives attachment to the ligament connecting it with the atlas. 

External to the fore part of the condyles are two fossae, in the bottom of which are two foramina, (anterior condyloid.) 
which look outwards and forwards, and transmit the hypoglossal nerves; behind them are also two larger pits, in which are 
"•enerallv, but not always, found foramina, (posterior condyloid.) which give passage to a vein and small artery ; sometimes a 
foramen exists at one side, and not at the other. External to each condyle is a rough surface, which overhangs the transverse 
processes of the vertebrae, and of which it may be regarded as the "analogue ;" it gives insertion to the rectus lateralis muscle. 

The internal surface of the bone is marked by two lines — one vertical, extending from the upper angle of the bone to the 



1C 

great foramen, and the other transverse from one lateral angle to the other. These interseet towards the centred point (internal 
„ dpial pro.uberance.) and mark off four pits, of which the upper pair (superior oecp.tal foss.) recetve «h< , post no lobe of £. 
Tain, and the lower (inferior oeeipi.nl fosste) lodge the lateral lobes of ,he cerebel urn : the supertor^ hue and .he .wo . nsve se 
ones Ire generally grooved, and eorrespond with .he course of .he longi.udtnal and lateral smuses. The mfenor one gives attach- 
In. .o ttefa x c y er g ebe,li. The a„.erior border of .he foramen magnum is s.ighdy excavated, »"7™— I m h 
basilar groove, a shallow excavation on the surface of the basilar process, which supporfs the medulla oblongat a dose , the 
margin of .he foramen are the anterior condyloid foramina, and a little external to .. are .wo fossa,, martong .he .erm.nat.ons of 

* e ' a The al .htkTrLgular process, which projects forward into .he base of .he stall from .he foramen, is called th< ■basilar process; 
i,s margins are rough, and [contiguous .o .he pars pe.rosa of .he temporal bone; its nnder surface presents shgh. depress,o„s for 
the insertion of muscles, and the upper one the shallow groove just noticed. 

PLATE VIII. 

Ligaments of the articulations between the occipital bone, the atlas and the axis, and of the lower jaw. 

Fig. 1. The ligaments connecting the occipital bone, the atlas and the axis, seen from the anterior aspect. 

No. 1. Section of the basilar process of the occipital bone. 2, 2. Sections of the extremity of the petrous portion of the temporal bones. 
3, 3. The transverse processes of the atlas. 4, 4. The axis. 5, 5. The third cervical vertebra. 6. The round, or accessory anterior 
occipito-atloidean ligament. 7, 7. The broad anterior occipito-atloidean ligament. 8, 8. Capsular ligaments of the oceipito-atloi- 
dean articulation. 9, 9. The anterior atlo-axoid ligament. 10, 10. Capsular ligaments of the atlo-axoid articulation : on the right 
side the articulation is laid open, in order to show the articulating surfaces. 11,11. Capsular ligaments of the articulation between 
the second and third vertebrae. 12. The commencement of the anterior common ligament. 

Fig. 2. The ligaments of the occipital bone, the atlas, and the axis, seen from behind. 

No. 1. A part of the occipital bone. 2. The posterior arch of the atlas. 3, 3. Its transverse processes. 4. The spinous process of the 
axis. 5, 5. Its laminae. 6, 6. Its rudimentary transverse processes. 7, 7. The third cervical vertebra. 8. The posterior occi- 
pito-atloidean ligament. 9, 9. The vertebral arteries, passing beneath an arch at each side, formed by this ligament. 10. The 
posterior atlo-axoidean ligament. 11, 11. The atlo-axoidean capsular ligaments. 12. One of the capsular ligaments of the articu- 
lation between the second and third vertebrae ; the other, 13, is laid open. 

Fig. 3. The upper part of the vertebral canal, opened from behind by removing a part of the arches of the vertebrae, in order to show the 
occipito-axoidean ligament. 

No. 1. The basilar portion of the sphenoid bone. 2, 2. The foramen lacerum posterius. 3, 3. The anterior condyloid foramina. 4, 4. 
The occipito-axoidean ligament. *5. A slight projection of this ligament, formed by the odontoid process. 6,6. The cut surfaces 
of the posterior arch of the atlas. 7, 7. The transverse processes of the atlas. 8, 8. The capsular ligaments of the occipito-atloi- 
dean articulation. 9, 9. The cut extremities of the laminae of the axis. 10, 10. The capsular ligaments of the articulation between 
the atlas and the second cervical vertebra. 

Fig. 4. The ligaments brought into view on the removal of the occipito-axoidean ligament. The section is the same as in the preceding 
figure. 

No. 1. A small portion of the occipito-axoidean ligament. 2. The transverse ligament of the atlas. 3, 3. The vertical fibres of the 
transverse ligament, which have gained for it the designation of the cruciform ligament. 4, 4. The odontoid ligaments, connecting 
the apex of the odontoid process with the inner surface of the condyles of the occipital bone. 5, 5. Occipito-atloidean capsular liga- 
ments. 6. 6. Capsular ligaments of the articulation between the atlas and the second cervical vertebra. 

Fig. 5. The ligaments of the occipital bone, atlas, and axis, examined by means of a vertical section. 

No. 1. The internal surface of a part of the base of the skull lined by dura mater. 2. One of the anterior condyloid foramina. 3. Section 
of the basilar process of the occipital bone. 4. Section of the posterior part of the occipital bone. 5. The cut surface of the anterior 
arch of the atlas. 6. The cut surface of the posterior arch. 7. Vertical section of the body of the axis and of the odontoid process. 
8. Cut surface of its arch. 9,9. Section of the third cervical vertebra. 10. Section of the anterior occipito-atloid ligament. 11. 
Section of the transverse ligament. 12. The superior vertical fasciculus of the transverse ligament. 13. The inferior vertical fasci- 
culus of the transverse ligament. 14, 14. The occipito-axoidean ligament. 15. The fan-shaped insertion of the right odontoid 
ligament. 16. The posterior occipito-atloidean ligament. 17. The right vertebral artery, passing beneath a tendinous arch formed 
by the posterior occipito-atloidean ligament. 18. Section of the anterior atlo-axoidean ligament. 19. The posterior atlo-axoidean 
ligament. 20. The commencement of the anterior common ligament. 21. Intervertebral substance between the bodies of the 
second and third cervical vertebrae. 22. The first ligamentum subflavum. 

Fig. 6. The atlas, seen from above, showing the situation of the transverse ligament, and the opening for the reception of the odontoid 
process of the axis. 

No. 1. The anterior arch of the atlas. 2. Its posterior arch. 3, 3. The lateral masses upon which the articular surfaces for the reception 
of the condyles of the occipital bone are seen. 4, 4. The transverse processes pierced by the foramina for the passage of the verte- 
bral arteries. 5. The transverse ligament. 6. The opening for the reception of the odontoid process. 7. The posterior opening 
of the ring of the atlas for the transmission of the spinal cord and its membranes. 

Fig. 7. The articulation of the lower jaw seen from the external surface. 

No. 1. A portion of the malar bone. 2. The zygoma. 3. The tubercle of the zygoma, which gives attachment to the external lateral 
ligament. 4. The external lateral ligament. 5. The neck of the lower jaw. 6. Its ramus. 7. Its coronoid process. 8. A part 



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The superior borders of the occipital bone are dentated and converge to a point, but are frequently interrupted by bony islets, 
(ossa triquetra — Wormiana ;) the inferior border at each side is divided into two parts by a prominent piece of bone, the jvgal 
eminence, which surmounts an excavation contributing with the temporal bone to form the jugular fossa. The superior angle is 
acute, and received into the retiring angle formed by the posterior border of the parietal bones ; the anterior is represented by the 
extremity of the basilar process ; the lateral angles, not very prominent, correspond with the line at which the postero-inferior 
angle of the parietal bone joins with the mastoid part of the temporal. 

Articulations. — The occipital articulates with six bones, viz., with the two parietal by its superior borders — the two temporal 
by the inferior — with the sphenoid by its basilar process — and with the atlas by the condyles. 

Attachments of muscles. — The posterior third of the superior curved line gives attachment to the trapezius ; its anterior 
two-thirds to the occipito-frontalis above, and to the sterno-mastoid below : the inner part of the space between the curved lines 
to the complexus : the external part to the splenius capitis : the space between the lower ridge and the great foramen to the recti 
majores and minores, and more outwardly to the obliquus superior: the under surface of the jugal eminences to the recti laterales: 
the fossae at the inferior surface of the basilar process to the recti antici, (majores and minores,) and still more anteriorly to the 
superior constrictor of the pharynx. 

Developement. — In the foetus at birth this bone consists of four distinct pieces, of which one represents the basilar process, 
two the lateral or condyloid portions, and one the posterior or expanded part. Hence it is usually said to commence by four 
points of ossification. Meckel, however, is of opinion that it has no fewer than eleven separate centres, eight of them being in the 
broad (squamous) part. This doubtless has existed in some specimens which he examined ; but ordinarily in the early stages of 
the developement there are found two ossific points in the lateral parts as above stated, one in the anterior or basilar, and four in 
the posterior broad part. 

The Parietal Bones. — The parietal bones (ossa parietalia) form a principal part of the roof of the skull ; they are of a 
square form, convex externally, concave internally, and present each two surfaces and four borders. The external surface rises 
towards its middle, where it presents a slight elevation, called the parietal eminence, below which is a curved line, forming part 
of the temporal ridge, and bounding a flat surface, which forms a part of the temporal fossa. At the upper and back part of the 
bone, usually about two lines from the sagittal suture, is a small hole, (foramen parietale,) which transmits a communicating 
vein ; its position is exceedingly variable ; even its existence is not constant. 

The internal surface of the bone is marked by branching lines, corresponding with the course of the middle meningeal 
artery, and by depressions for the convolutions of the brain. Towards its middle is a depression, " parietal fossa," corresponding 
with the eminence (parietal) on the outside. Along the superior border is a slight depression, which, with a similar one in the 
corresponding bone, forms a groove adapted to the course of the longitudinal sinus ; and in the same situation (in most skulls, 
particularly those of old persons) are some small pits corresponding with the so-named glandulae Pacchioni. 

The superior border is straight, and articulated with its fellow by a series of dentations ; the inferior border, concave and 
bevelled off at its outer margin, is overlapped by the squamous portion of the temporal bone ; the anterior unites with the frontal 
bone, and posterior with the occipital. 

The anterior inferior angle dips down to the great wing of the sphenoid bone, and presents a groove internally for the middle 
meningeal artery : the posterior inferior angle articulates with the mastoid part of the temporal bone, and presents internally 
a small part of the groove which lodges the lateral sinus. 

Each parietal bone gives attachment to the temporal muscle by that part of its surface which lies beneath the temporal ridge: 
the remainder of its outer surface is covered by the aponeurosis of the occipito-frontalis. 

Articulations. — It articulates with its fellow of the opposite side, and with the frontal, the sphenoid, the temporal, and the 
occipital bones. 

Developement. — Its growth proceeds from one ossific centre which corresponds with the parietal eminence. At birth the 

of the superior maxillary bone. 9. The mastoid process of the temporal bone. 10. The meatus auditorius externus. 11. The 

styloid process. 12. The stylo-maxillary ligament. 
Fig. 8. The articulation of the lower jaw seen from within. 
Nos. 1, 1. The cut surface of a section, including a part of the occipital, the petrous portion of the temporal, and the spinous process of 

the sphenoid bone. 2. The internal surface of the mastoid process. 3. The styloid process. 4. The stylo-maxillary ligament. 

5. The ramus of the lower jaw. 6. The internal lateral ligament of the articulation of the lower jaw. 7. The small arched 

opening which transmits the mylo-hyoidean nerve. 8. The neck of the lower jaw. 9. Its coronoid process. 
Fig. 9. A vertical section carried through the middle of the articulation of the lower jaw. 
Nos. 1, 1. Section of the temporal bone. 2. The interarticular fibro-cartilage dividing the joint into two synovial cavities. 3. The 

superior synovial cavity. 4. The inferior synovial cavity. 5. Cut surface of the head of the lower jaw. C. Ramus of the lower 

jaw. 7. Its coronoid process. 8. Its angle. 9. The styloid process of the temporal bone. 1.0. The stylo-maxillary ligament 

11. The internal surface of the mastoid process. 
Fig. 10. An interarticular fibro-cartilage removed from the articulation. 

Fig. 11. An interarticular fibro-cartilage pierced through its middle by a foramen, as is sometimes observed. 
Bones. — 3 



18 

antero-superior angles of these bones are not developed ; hence there exists an interstice between them and the still divided os 
frontis, which is called the " fontanelle," (fons, bregma.) 

The Frontal Bone.- The frontal bone, (os frontis, coronale,) situated at the anterior part of the skull, and upper part of the 
face, is divisible into two parts, (frontal and orbital,) differing in size and position; of these, one extends upwards towards the 
vertex, forming three fourths of the extent of the bone ; the other, inferior and horizontal in its direction, forms the roof of the 
orbits. To place the bone in its natural position, hold it so that the orbital plates shall look downwards, and the smooth convex 
surface forwards. 

PLATE IX. 

In this plate several views of the cranium are exhibited. 

Fig. 1 . An anterior view of the cranium and face. 

No. 1. The frontal bone. 2, 2. The parietal bone. 3, 3. The coronal suture uniting the frontal with the parietal bones. 4, 4. The 

upper part of the great ala of the sphenoid bone. 5, 5. The squamous portion of the temporal bone. 6, 6. The frontal eminence. 

7, 7. The superciliary ridge. 8. The nasal tuberosity. 9, 9. The supra-orbital ridge. 10. The supra-orbital notch of the right orbit. 

11. The internal angular process. 12. The external angular process. 13. The commencement of the temporal ridge — The numbers 

2, 4, and 5, are situated in the temporal fossa.— 14. The orbital plate of the frontal bone. 15. The nasal bones. 16. The superior 
maxillary bone. 17. Its nasal process. 18. The infra-orbital foramen. 19. Its malar process. 20. The canine fossa. 21. The 
incisive fossa. 22. The nasal spine. 23. The harmonia suture uniting the two superior maxillary bones. 24. The alveolar process. 
25. Median incisor tooth. 26. Lateral incisor. 27. Canine tooth. 28. The two bicuspides or small molars. 29. The great molars. 
30. The lachrymal bone. 31. The malar bone. 32. Its frontal process. 33. Its maxillary process. 34. Its zygomatic process. 
35. Its orbital process. 36. The orbital surface of the great ala of the sphenoid. 37. The sphenoidal fissure of the orbit. 38. The 
depression on the orbital plate of the frontal bone beneath its external angular process for the lachrymal gland. 39. The depression 
beneath the internal angular process, for the pulley of the trochlearis muscle. 40. The middle turbinated bone. 41. The inferior 
turbinated bone. 42. The vomer. 43. The body of the lower jaw. 44. Its symphysis. 45. The depression by the side of the 
symphysis for the origin of the depressor labii inferioris muscle. 46. The incisive fossa, for the levator labii inferioris. 47. The 
mental foramen. 48. The alveolar process ; the teeth are the same as in the upper jaw. 49. The ramus of the lower jaw. 
50. The angle of the lower jaw. 

Fig. 2. A side view of the cranium and face. 

The numbers of reference, from 1 to 50, are the same as in the preceding figure. No. 51. The sagittal suture, connecting the two 
parietal bones. 52. The temporal ridge upon the parietal bone. 53. The anterior inferior angle of the parietal bone. 54. The 
posterior inferior angle. 55. The squamous suture. 56. The zygoma. 57. Its tubercle. 58. Its superior root, continuous with 
the temporal ridge. 59. The meatus auditorius externus. 60. The mastoid process. 61. The styloid process. 62. The occipital 
bone. 63. The lambdoidal suture. 64. The additamentum suturae lambdoidalis. 65. The additamentum suturae squamosae. 
66. Condyle of the lower jaw. 67. Coronoid process of the lower jaw. 68. Semilunar notch of the lower jaw. 

Fig. 3. Base of the skull. 

Nos. 1, 1. The body of the lower jaw. 2, 2. The depressions near the symphysis, for the attachment of the digastric muscles. 

3. Tubercles for the attachment of the genio-hyoid and genio-hyo-glossi muscles. 4, 4. The molar ridge of the lower jaw, seen 
upon one side. 5. The angle. 6. The condyle. 7. Part of the malar bone. 8. The zygomatic arch. 9, 9. The palatal pro- 
cesses of the superior maxillary bones. 10. The naso-palatine foramen. 11, 11. The palatal processes of the palate bones. 
12, 12. The posterior palatine foramina. 13. The palate spine. 14. The vomer. 15, 15. The posterior nares. 16, 16. The 
internal pterygoid plates of the sphenoid bone. 17, 17. The hamular processes. 18, 18. The external pterygoid plates; the 
figures are placed in the pterygoid fossae. 19. The zygomatic fossa of one side. 20. The foramen ovale. 21. The foramen 
lacerum basis cranii. 22. The petrous portion of the temporal bone. 23. The carotid foramen. 24, 24. The foramen lacerum 
posterius. 25. The vaginal process. 26. The stylo-mastoid foramen. 27. The meatus auditorius externus. 28. The mastoid 
process. 29. The digastric fossa. 30. Part of the additamentum suturae lambdoidalis. 31. The transverse process of the occipital 
bone. 32. The anterior condyloid foramen. 33, 33. The condyles of the occipital bone. 34. The posterior condyloid foramen. 
35. The foramen magnum. 36. The basilar process of the occipital bone. 37, 37. The inferior curved line of the occipital bone. 
38, 38. The superior curved line. 39. The occipital tuberosity. 40, 40. The occipital spine. 41. The occipital bone. 42, 42. 
Part of the lambdoidal suture. 43. The parietal bone. 44. Mastoid portion of the temporal bone. 

Fig. 4. Vertical and longitudinal section of the cranium. 

No. 1. The frontal bone. 2. The frontal sinus. 3. Nasal bone. 4. Crista galli. 5. Central lamella of the ethmoid bone. 6. Vomer. 
7. The inferior turbinated bone. 8. The palate. 9. The naso-palatine canal. 10. Pterygoid process. 11. Section of the basilar 
process of the ompital bone. 12. Sphenoidal cells. 13. Anterior clinoid process. 14. Roof of the ri<rht orbit. 15, 15 Grooves 
for the lodgment of the branches of the arteria meningea media. 16. Parietal bone, divided through the sagittal suture. 17. The 
occipital bone. 18. Border of the foramen magnum. 19. Petrous portion of the temporal bone. 20. The meatus auditors 
internus. 21. Foramen lacerum posterius or jugular foramen. 22. The groove for the lateral sinus. 23. The mastoid process. 

Fig. 5. A section showing the right nasal fossa. r 

No. 1 Part of the frontal bone 2 Frontal sinus. 3 Nasal bone. 4. Crista galli. 5, 5. The upper part of the central lamella of 
the ethmoid- 6. Sphenoid cells 7. Opening of the sphenoid cells into the superior meatus of the nose. 8. Anterior clinoid 
process. 9 Basilar process of the occipital bone. 10. Superior meatus of the nares. 11. The sphenopalatine foramen. 12. The 
middle turbinated bone. 13, 13. The middle meatus of the nasal fossa. 14. The inferior turbinated bone. 15. The inferior 
meatus. 16. The pterygoid process. 17. The cut edge of the palate. 18. The naso-palatine canal. 19. The under surface of 
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The external surface of the frontal part is smooth, and presents on each side a slight elevation, named frontal eminence, 
which corresponds with the most prominent part of the forehead : beneath this is an arched depression, bounded below by a pro- 
minent curved line, called the superciliary ridge, or arch, which is more or less prominent in different individuals. Immediately 
beneath this is the margin of the orbit {orbital arch,) which is better denned towards its outer part, where it curves down to the 
malar bone, and forms the external angular process, than at its inner portion, where it gradually subsides towards the root of the 
nose. Towards the inner third of the orbital arch is a small foramen, {supra-orbital,) or sometimes a notch crossed by a liga 
ment, which transmits the supra-orbital nerve and artery. 

Between the superciliary ridges is the nasal eminence, or glabella, which is prominent in proportion to the size of the frontal 
sinuses ; it is bounded inferiorly by a rough surface which articulates with the nasal bones and the ascending processes of the 
superior maxilla. From this surface projects downwards in the median line a fiat thin process, called the nasal spine ; it articu- 
lates in front with the nasal bones, and behind with the perpendicular lamella of the ethmoid. 

The internal surface of this part of the bone is concave, and presents along the median line a groove corresponding with the 
longitudinal sinus. The margins of the groove gradually approach towards the fore part of the bone, and in some cases unite so 
as to form a ridge ; but in others the groove, narrowed almost to a line, continues apparent down to the foramen caecum. In 
either case it gives attachment to the falx ; this ridge terminates in a minute foramen, called foramen cxcum, from its having been 
supposed to be merely a cul-de-sac, but it is in reality pervious, and lodges a small spurlike process of the dura mater, and trans- 
mits a vein which enters the sinus from the nasal fossae. 

The orbital plates or processes are smooth and concave at their inferior surface ; the superior or cerebral is convex, and marked 
more or less in different instances by elevations and depressions corresponding with the sulci and convolutions of the anterior lobes 
of the brain which rest upon them. They are separated by a deep excavation, (incisura ethmoidalis,) which receives within it 
the cribriform plate of the ethmoid bone, and round its margins are several cells which complete the cavities lodged within the 
lateral parts of the last-named bone. In this margin may also be observed two foramina, {anterior and posterior orbital,) which 
are common to the frontal and ethmoid bones, as their contiguous margins contribute to their formation. The anterior one trans- 
mits the nasal twig of the ophthalmic nerve, and the anterior ethmoidal artery ; the other, the posterior ethmoidal artery and vein. 
Each orbital plate is bounded externally by a thick well-marked prominence, called the external angular process ; and internally 
by a depressed and smooth one, {internal angular process.) Near the inner one is a slight depression, to which is attached the 
cartilaginous pulley of the trochlearis muscle ; near the outer and within the orbit, is a depression for the lodgment of the lachrymal 
gland ; the external side of this process is slightly hollowed, and forms part of the temporal fossa. 

The thickness of the frontal bone varies considerably in different parts of it. The orbital plates are thin and translucent ; the 
nasal and external angular processes are thick and prominent. The upper or broad part is thinner at the frontal eminences than 
elsewhere, if these are well-marked, so as to indicate a full developement of the corresponding cerebral parts. In childhood the 
two tables are separated only by the diploe, as in other bones ; but, in adult age, an interval exists between them at the middle 
line over the nasal process, and extending outwards for some way under the superciliary ridges. This interval, the extent of which 
varies in different individuals, is divided by a ridge of bone into two parts or cavities called the frontal sinuses; they are lined 
by mucous membrane, and communicate with the anterior ethmoidal cells. 

Articulations. — The frontal articulates with twelve bones; superiorly with the two parietal, laterally and behind with the 
sphenoid, inferiorly with the ethmoid; with the nasal bones by the nasal spine ; with the ossa unguis ; with the ascending process 
of the superior maxillary bones ; and with the malar bones. The mode of articulation differs in different parts of its circumference. 
Thus, the superior border is found to overlap and rest on the parietal bones, whilst towards the lateral and inferior parts the 
exterior table ©f the bone is bevelled off, and is covered in by the parietal. The posterior border of the orbital plates, straight and 
squamous, is in a manner inserted between the margins of the two alas of the sphenoid bone, with each of which it articulates. 

PLATE X. 

This plate exhibits the occipital and parietal bones, with the interior of the base of the skull. 

Fig. 1. The external surface of the occipital bone. 

No. 1. The protuberance of the occipital bone. 2, 2. Its spine. 3, 3. The superior curved line. 4, 4. The surface above the superior 
curved line to which the occipito-frontalis muscles are attached. 5, 5. The inferior curved line. 6, G. The rough surface to which 
the complexi muscles are attached. 7, 1. The rough surface to which the splenii capitis are attached. 8, 8. The rough surface for 
the recti postici and obliqui superiores. 9. The foramen magnum. 10, 10. The condyles of the occipital bone. 11, 11. The rough 
surface within the condyles, to which the odontoid ligaments are attached. 12, 12. The inner openings of the anterior condyloid 
foramina. 13. The basilar process, its under surface. 14. Its upper and concave surface, upon which the medulla oblongata raato 
15, 15. The posterior condyloid foramina. 1G, 16. The transverse process of the occipital bone. 17, 17. The superior borders of 
the bone. 18,18. Its inferior borders. 19,19. The notches corresponding with the jugular foramina. 

Fig. 2. The internal surface of the occipital bone ; after Cheselden. 

Nos. 1,1. The cerebral fossae, for lodging the posterior lobes of the cerebrum. 2, 3. The cerebellar fosBte, for the lateral lobes of the 



20 

Attachment of muscles.— It gives attachment to the corrugator supercilii— to a small part of the temporal and of the orbi- 
cularis palpebrarum. 

Developement.— This bone begins by two osseous points corresponding with the frontal eminences, ine lateral pieces 
formed by the spreading of the ossification ultimately become united along the middle by a straight suture, which runs from the 
vertex, where it is continuous with the sagittal suture, down to the nose. It is generally obliterated at an early period. 

The Temporal Bone.— -The temporal bones, two in number, are so named because they occupy that part of the head on 
which the hair first becomes white, and thus indicates the ravages of time, (ossa temporis.) 

The temporal bone (os temporis) is placed at the side and basis of the skull. When viewed in its natural position, it presents 
two portions, one at the side of the skull, towards its middle and lower part, which is flat and vertical in its direction ; whilst the 

cerebellum. 3. The superior arm of the crucial ridge : this ridge is grooved for the superior longitudinal sinus, and to the borders 
of the groove the falx cerebri is attached. 4. The inferior arm of the crucial ridge, for the falx cerebelli and cerebellar sinuses. 
5, 5. The transverse ridge, for the tentorium cerebelli and lateral sinuses. 6. The internal occipital protuberance. 7, 7. The 
superior borders of the bone. 8, 8. Its inferior borders. 9, 9. The jugular eminences. 10. The jugular fossa of the right side. 
11. The border of the bone which articulates with the petrous portion of the temporal bone. 12. The anterior condyloid foramen of 
the right side. 13, 13. The condyles. 14. The anterior margin of the foramen magnum. 15. The under surface of the basilar 
process. 16. Its lateral surface. 17. The surface which articulates with the sphenoid bone. 
Fig. 3. The external surface of the right parietal bone. 

No. 1. The parietal eminence. 2, 2. The temporal ridge. 3, 3. The rough surface above the ridge, upon which the aponeurosis of the 
occipito-frontalis muscle rests. 4, 4. The smooth surface below the ridge, that gives attachment to the temporal muscle. 5. The 
superior or sagittal border of the bone. 6. The parietal foramen. 7. The anterior and concave border of the parietal bone. 8. The 
posterior and somewhat convex border. 9. The inferior or squamous border. 10, 10. The grooves upon this part of the bone 
correspond with ridges upon the squamous border of the temporal. 11. The anterior and inferior angle of the bone. 12. The 
posterior and inferior angle. 
Fig. 4. The left parietal bone seen upon its internal surface ; after Cheselden. 

Nos. 1, 1. The grooves for lodging the ramifications of the arteria meningea media. 2. At the anterior and inferior angle of the bone, 
the groove for the main trunk of this artery is converted into a canal. 3. A groove upon the posterior and inferior angle for the 
lodgment of the lateral sinus. 4, 4. A partial groove, completed by the articulation of the two parietal bones, and serving for the 
lodgment of the superior longitudinal sinus. 5. The superior or sagittal border of the bone. 6. The anterior or coronal border; 
the formation of the serrations at the expense of the outer table is well exhibited. 7. The posterior or lambdoidal border. 8. The 
inferior or squamous border. 
Fig. 5. A view of the interior of the base of the skull ; the calvarium having been removed. 

Nos. 1, 1. The cut surface of the frontal bone; in this section, the structure of the cranial bones, consisting of two tables and an inter- 
vening cellular part, the diploe' is well seen. 2, 2. The parietal bone. 3, 3. The squamous part of the temporal bone; in this bone 
the diploe is not present. 4, 4. The occipital bone. 5. A part of the ridge on the internal surface of the frontal bone, which gives 
attachment to the falx cerebri, and supports the commencement of the longitudinal sinus. 6. The foramen caecum. 7. The crista 
galli process of the ethmoid bone. 8, 8. The cribriform plates with their foramina. 9, 9. The orbital plates of the frontal bone; 
the depressions on these plates are the digital fossae. 10. The ethmoidal spine of the sphenoid bone. 11, 11. The lesser wings 
of the sphenoid. 12, 12. The optic foramina. 13, 13. The anterior clinoid processes. 14. The processus olivaris. — The whole 
of the preceding figures, from No. 4, are situated in the anterior fossa of the base of the cranium. Nos. 15, 15, with 13, 13, and 14, 
form the posterior boundary of this fossa, and the anterior boundary of the middle fossa of the base of the cranium. The border, 
15, 15, is received into the fissure of Sylvius on each side of the base of the brain. — 16. The cella Turcica. 17, 17. The depres- 
sion upon each side of the cella Turcica, which lodges the last turn of the internal carotid artery. 18, 18. The depression upon each 
side of the cella Turcica, which supports the internal carotid artery and the cavernous sinuses. 19, 19. The foramen rotundum of 
the sphenoid bone. 20, 20. The foramen ovale. 21, 21. The foramen spinosum. 22, 22. The foramen laaerum basis cranii. 
23, 23. The cerebral surface of the greater ala of the sphenoid bone. 24, 24. The internal surface of the squamous portion of the 
temporal bone. 25, 25. The anterior surface of the petrous portion of the temporal bone. 26, 26. The eminence upon the anterior 
surface of the petrous portion of the temporal bone, which marks the situation of the superior or perpendicular semicircular canal. 
27, 27. The groove which leads to the hiatus Fallopii. — The whole of the preceding figures, from No. 16, are situated in the middle 
fossa of the base of the cranium. — 28, 28. The superior border of the petrous portion of the temporal bone, for the attachment of the 
tentorium cerebelli. 29, 29. The notch near the extremity of the petrous portion of the temporal bone, which supports the fifth nerve. 
30, 30. The posterior clinoid processes. — The figures 28, 29, and 30, at each side, mark the posterior boundary of the middle fossa 
of the base of the cranium and the anterior boundary of the posterior fossa.— 31. The basilar portion of the sphenoid and occipital 
bones, rendered concave for the support of the pons Varolii and medulla oblongata. 32, 32. The posterior surface of the petrous 
portion of the temporal bone. 33, 33. The meatus auditorius internus. 34. The aqueductus vestibuli on the right petrous bone. 
35, 35. The groove for the inferior petrosal sinus. 36, 36. The jugular fossa. 37. A part of the jugular foramen of the right side. 
38, 38. The groove for the lateral sinus, on the occipital bone. 39, 39. The same groove on the mastoid portion of the temporal 
bone. 40, 40. The same groove upon the posterior and inferior angle of the parietal bone. 41,41. The groove upon the occipital 
portion of the occipital bone. 42. The internal occipital protuberance. 43. The inferior arm of the crucial ridge of the occipital 
bone. 14, 44. Cerebellar fossae. 45. The foramen magnum. 46,46. The anterior condyloid foramen.— The whole of the preced- 
ing figures, from No. 31, are situated in the posterior fossa of the base of the cranium ; the numbers 40, 41, and 42, forming its 
posterior boundary. — 17. The superior arm of the crucial ridge of the occipital bone. 48. The cerebral fossa of the right side of 
the occipital bone. 49. The arch of the zygoma. 



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21 

other is horizontal and projects inwards so as to be wedged between the occipital and sphenoid bones. But to facilitate its descrip- 
tion, it may be divided into three parts, adopting the division which obtains in infancy before the ossification is complete. One 
is superior, flat, scale-like, and named the squamous portion, (squama, a scale ;) another posterior, thick at its base, but tapering 
downward like a nipple, the mastoid part ; the third, called petrous from its hardness, is internal and intermediate, projecting into 
the basis of the skull. 

The squamous portion, (pars squamosa,) by its external surface which is smooth, forms part of the temporal fossa, and is 
bounded above by an arched border, below by a horizontal process called " zygoma." The inner surface of the squamous part 
of the bone, slightly concave in its general outline, is marked by cerebral impressions like the other bones of the head, and by 

PLATE XL 

The frontal and temporal bones in the adult and in the foetus. 

Fig. 1. The frontal bone seen upon its anterior aspect: after ourgery. 

Nos. 1, 1. The frontal eminences. 2, 2. The superciliary ridges. 3. The nasal eminence or tuberosity. 4, 4. The supra-orbital 
ridges. 5, 5. The supra-orbital notches. 6. The internal angular process of one side. 7. The rough surface for articulation with 
the nasal bones. 8. The nasal spine. 9. The external angular process. 10. The temporal ridge. 11. A part of the temporal 
fossa. 12, 12. The border which articulates with the parietal bones. 

Fig. 2. The frontal bone seen upon its internal aspect: after Cheselden. 

No. 1. The longitudinal ridge which gives attachment to the falx cerebri. The dark line in the course of this ridge indicates the exist- 
ence of a median suture in this bone. 2. Depressions for glandulse Pacchioni. 3. The nasal spine. 1, 4. The borders of the 
ethmoidal fissure. 5, 5. The openings into the frontal sinuses. 6, 6. The orbital plates. 7, 7. The supra-orbital ridges. 8. The 
internal angular process of one side. 9. The external angular process. 10. Apart of the temporal fossa. 11, 11. The border 
which articulates with the lesser wing of the sphenoid. 12, 12. The border which articulates with the greater wing of the sphe- 
noid. 13, 13. The border which articulates with the parietal bones. 

Fig. 3. The frontal bones seen upon its inferior or orbito-nasal aspect: after Cheselden. 

Nos. 1, 1. The frontal portion of the bone. 2. A line indicating the existence of a frontal suture. 3. The nasal eminence or tuberosity. 
4. The rough surface which articulates with the nasal bones, and the nasal spine. 5. The ethmoidal fissure. 6, 6. The borders 
of the ethmoidal fissure. 7, 7. The orbital plates. 8, 8. The supra-orbital ridges. 9. The internal angular process of one side. 
10. The depression for lodging the cartilaginous pulley of the trochlearis muscle. 11. Two supra-orbital foramina. 12. The 
external angular process. 13. The lachrymal fossa. 14. The temporal ridge. 15. Part of the temporal fossa. 16, 16. The 
border which articulates with the sphenoid bone. 

Fig. 4. An anterior view of the foetal skull, showing the mode of developement of the frontal bone by two lateral portions. 

Nos. 1,1. The lateral portions of the frontal bone. 2. The line of approximation of the two lateral portions; when union is incom- 
plete in the adult, a frontal suture is met with in this situation. 3, 3. The parietal bones. 4. The anterior fontanelle. 5. The 
extremity of the great ala of the sphenoid of one side. 6. The temporal bone of the same side. 7. The nasal bones. 8, 8. The 
superior maxillary bones. 9, 9. The malar bones. 10, 10. The inferior maxillary bone consisting of two lateral portions. 

Fig. 5. The temporal bone of the right side, viewed upon its external surface: after Bourgery. 

No. 1. The squamous portion. 2. The zygoma. 3. The tubercle of the zygoma. 4. The superior root of the zygoma, which serves 
to mark the separation of the squamous from the mastoid portion of the temporal bone. 5. The middle root of the zygoma. 6. The 
eminentia articularis, with which the anterior root is continuous. 7. The mastoid portion of the temporal bone. 8. The mastoid 
process. 9. The mastoid foramen. 10. The meatus auditorius externus. 11. The processus auditorius. 12. The styloid process. 

13. The vaginal process. 14. The glenoid fossa. 

Fig. 6. The temporal bone of the right side, seen upon its internal aspect: after Cheselden. 

No. 1. The squamous portion. 2. A groove for the posterior branch of the arteria meningea media. 3, 3. The squamous border, which 
articulates with the lower border of the parietal bone. 4. The extremity of the zygoma seen projecting beyond the anterior border 
of the temporal bone. 5. The mastoid portion of the bone. 6, 6. The groove for the lateral sinus. 7. The internal termination 
of the mastoid foramen. 8. The petrous portion of the temporal bone. 9. The meatus auditorius internus. 10. A small notch 
for the insertion of a process of dura mater. 11. The opening of the aquaeductus vestibuli. 12. Groove for the superior petrosal 
sinus. 13. The elevation corresponding with the superior semicircular canal. 14. Groove for the inferior petrosal sinus. 15. The 
irregular notch which forms the anterior boundary of the jugular foramen. 16. The extremity of the styloid process. 

Fig. 7. The inferior or basial surface of the right temporal bone. 

No. 1. The squamous portion. 2. The zygoma. 3. Its tubercle. 4. The eminentia articularis. 5. The glenoid fossa; its condy- 
loid portion. 6. Its parotid portion. 7. The glenoid fissure. 8. The opening for the Eustachian tube. 9. The vaginal process. 
10. The styloid process. 11. The lower border of the processus auditorius. 12. The mastoid process. 13. The digastric fossa. 

14. The occipital groove. 15. The stylo-mastoid foramen. 16. The jugular fossa. 17. The carotid foramen. 18. The petrous 
portion of the temporal bone. 

Fig. 8. The left temporal bone of the foetus, showing three of the pieces of which it consists at an early period. 

No. 1. The squamous portion. 2. The mastoid portion. 3. The auditory portion. 

Fig. 9. The petrous portion of the temporal bone of a foetus : after Cheselden. 

Fig. 10. The parietal bone of a foetus, showing the radiated disposition of the osseous fibres of which it is composed at this early period : 

after Cheselden. 
I'k,. 1 1. The occipital bone of a foetus, showing the four pieces of which it consists at an early period : after Cheselden. 
No. 1. The occipital portion. 2,2. The condyloid portions. 3. The basilar portion. 



22 

slight linear grooves for the branches of the middle meningeal artery. Its upper edge is bevelled off so as to form a thin scale 
which overlies the parietal bone. 

The zygoma, or zygomatic process, (friw to connect or yoke together,) forms a yoke connecting the temporal with the 
malar bone, and under which the temporal muscle passes ; it is broad posteriorly at its base, where it projects outward from the 
squamous part of the bone, but soon narrows, and turns forward ; its outer surface is convex and subcutaneous, the inner surface 
is concave and bounds the temporal fossa; the superior margin, very thin, gives attachment to the temporal fascia; the inferior 
one is thicker and shorter, owing to the end of the process being bevelled off so as to rest on the malar bone, with which it articu- 
lates. At its base the upper surface is concave, and supports the posterior border of the temporal muscle. The under surface 

PLATE XII. 

Bones of the head and face. 4 

Fig. 1. An anterior view of the sphenoid bone: after Cheselden. 

No. 1. The ethmoidal spine. 2. The lesser wing of one side. 3. The sphenoidal spongy bone of one side closing the sphenoidal cells. 

4. The sphenoidal cells exposed upon the opposite side. 5. The rostrum. 6. The sphenoidal fissure. 7. The orbital surface of 
the great ala of the sphenoid bone. 8. The temporal surface. 9. The pterygoid crest. 10. The zygomatic portion of the external 
surface of the great ala of the sphenoid. 11. The foramen rotundum. 12. The Vidian foramen. 13. The smooth surface upon 
the anterior surface of the root of the pterygoid process against which Meckel's ganglion rests. 14. The pterygo-palatine canal. 

15. The internal pterygoid plate of the pterygoid process. 1G. Its hamular process. 17. The external pterygoid plate. 18. The 
triangular notch between the pterygoid plates for the reception of the tuberosity of the palate bone. 19. The foramen ovale. 20. A 
notch, which in this bone would seem fo represent the spinous foramen. 

Fig. 2. The sphenoid bone seen upon its posterior aspect : after Cheselden. 

No. 1. The basilar portion of the sphenoid bone. 2. The surface which articulates with the basilar process of the occipital bone. 
3, 3. The posterior clinoid processes. 4, 4. The anterior clinoid processes. 5, 5. The lesser wings of the sphenoid. G. The 
optic foramen on the right side. 7, 7. The sphenoidal fissure. 8. The great ala of the sphenoid of one side ; its cerebral surface. 
9. The spinous process. 10. The posterior opening of the Vidian canal. 11. The pterygo-palatine canal. 12. The pterygoid 
fossa. 13. The internal pterygoid plate of the pterygoid process. 14. The hamular process. 15. The external pterygoid plate. 

Fig. 3. The superior or cerebral surface of the sphenoid bone: after Cheselden. 

No. 1. The ethmoidal spine. 2. The olivary process. 3,3. The lesser wings. 4,4. The anterior clinoid processes. 5,5. The 
optic foramina. G, G. The depression for the last turn of the internal carotid artery. 7. The sella Turcica. 8, 8. The posterior 
clinoid processes. 9. The basilar portion of the bone. 10. The surface which articulates with the basilar process of the occipital 
bone. 11, 11. The groove upon the side of the body of the sphenoid bone for the horizontal portion of the internal carotid artery. 
12. The sphenoidal fissure of one side. 13. The foramen rotundum. 14. The foramen ovale. 15. The foramen spinosum. 

16. The spinous process of the sphenoid. 17. The spine at the extremity of the spinous process. 18. The great ala of the 
sphenoid; its cerebral surface. 19. The internal pterygoid plate of the pterygoid process. 20. The hamular process. 21. The 
external pterygoid plate. 

Fig. 4. Cerebral surface of the sphenoid bone of a foetus. 

No. 1. The anterior portion of the body. 2, 2. The rudimentary lesser wings. 3. The posterior portion of the body. 4, 4. Rudimen- 
tary pterygoid processes. 5, 5. Rudimentary greater wings. 6, 6. Rudimentary spinous processes. 

Fig. 5. The ethmoid bone, seen upon its upper and lateral surface: after Cheselden. 

No. 1. The crista galli process. 2, 2. The cribriform plate. 3, 3. The superior borders of the bone. 4. The os planum. 5. The 
anterior cells, completed by the lachrymal bone. 6, 6. Posterior ethmoidal cells. 7. The anterior extremity of the central 
lamella. 

Fig. 6. The ethmoid bone, seen upon its inferior and lateral surface : after Cheselden. 

Nos. 1, 1. The central perpendicular lamella. 2. The os planum. 3. The superior turbinated bone. 4. The middle turbinated bone. 

5. The superior meatus of the nose. 

Fig. 7. The ethmoid bone, seen upon its posterior surface. 

No. 1. The crista galli. 2, 2. The cribriform plates. 3, 3. The upper borders of the bone. 4, 4. The os planum. 5, 5. The lateral 

masses. 6. The central lamella. 7, 7. The superior turbinated bones. 8, 8. The middle turbinated bones. 9, 9. The superior 

meatuses. 
Fig. 8. The two nasal bones, articulated and seen upon their under surface: after Cheselden. 
No. 1. The upper thick extremity of the bones. 2, 2. The irregular free margin. 3, 3. The lateral borders which articulate with the 

superior maxillary bones. 4, 4. The groove upon the under surface of each nasal bone, for the external branch of the nasal nerve. 
Fig. 9. The lachrymal bone; its external surface: after Cheselden. 

No. 1. The crest which divides the bone into two portions. 2. The orbital portion. 3. The lachrymal portion, grooved for the reception 

of the lachrymal sac. 
Fig. 10. The lachrymal bone; its internal surface: after Cheselden. 
No. 1. A part of the vertical crest of the external surface. 
Fig. 11. The inferior turbinated bone, seen upon its convex surface. 
Fig. 12. The malar bone of the right side, seen upon its external surface. 
No. 1. The frontal process 2. The superior maxillary process. 3. The zygomatic process. 4. One of the foramina for the transin.s- 

sion 01 the filaments of nerves and small arteries. 
Fig. 13. The malar bone of the right side, seen upon its internal surface: after Cheselden. 



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23 

forms the border of the glenoid cavity ; here it presents two roots, of which one runs horizontally backwards, forming the outer 
margin of the glenoid cavity, whilst the other turns inwards and forms the anterior border of that cavity. At the point of division 
is a slight tubercle, which gives attachment to the external lateral ligament of the lower jaw. Now the anterior root widens and 
subsides, becoming concave from without inwards and convex from before backwards, as it forms part of the articular surface 
upon which the lower jaw-bone moves ; in its natural condition it is covered with cartilage. The other root, which is continued 
horizontally backwards, bifurcates, one part turning inwards to the fissura Glasseri, whilst the other gradually subsides as it passes 
backwards over the auditory tube, yet marks the separation between the squamous and mastoid portions of the bone. The glenoid 
fossa, (y*n vf i> a shallow pit,) marked off as here indicated, is elongated from without inwards, and divided into two parts by a 
fissure, (fissura Glasseri,) which transmits the chorda tympani nerve, laxator tympani muscle, and gives attachment to the pro- 
cessus gracilis of the malleus. The part before the fissure is smooth, and articulates with the lower jaw ; the remainder lodges a 
process of the parotid gland. 

The mastoid part of the bone externally is rough, for the attachment of muscles, and prolonged downwards, forming the 
mastoid or nipple-shaped process, (/ia«o S , a nipple : fiSo $) ) from which this division of the bone is named. This process overhangs 
a groove, (digastric fossa,) for the attachment of the digastricus muscle ; close to this is a slight groove, the occipital groove. 
When viewed at its inner surface, the mastoid part presents a broad and generally a deep groove, which curves forwards and 
downwards ; it here supports part of the lateral sinus. It is usually pierced by a foramen, (mastoideum,) which opens into the 
sinus from the outer surface, commencing near the posterior border of the bone. The size and position of this hole vary in 
different instances ; it sometimes exists at one side and not at the other. 

The petrous part, pars petrosa, (rff*po 5 , a stone,) forms a triangular pyramid (pyramis trigona) which projects into the base 
of the skull forwards and inwards ; it presents a base, an apex, (truncated,) three surfaces, and three borders. In the base is 
situated the orifice of the auditory canal, which is bounded above by the posterior root of the zygoma ; inferiorly, and in the 
greatest part of its circumference, by a curved uneven lamella, (auditory process,) to which the cartilage of the ear is attached : 
this process is in the foetus a separate piece. The canal itself, (meatus auditorius externus,) narrower in the middle than at its 
extremities, is directed obliquely forwards and inwards, and leads into the tympanum. The apex or inner end of the pars 
petrosa, rough, irregular, and, as it were, truncated, forms part of the foramen lacerum medium, and is pierced by the termina- 
tion of the carotid canal, (canalis caroticus:) — this canal commences in the inferior surface of the bone anterior and internal to 
the jugular fossa, ascends at first perpendicularly, but soon turns horizontally forwards and inwards to the apex, where it ends. 

The anterior surface of the petrous portion forms part of the middle fossa in the base of the skull, where it looks obliquely 
upwards and forwards. Towards the apex it is slightly grooved, where it corresponds with the ganglion of the fifth pair of 
nerves, (Casserian.) A narrow groove is seen to run obliquely backwards and outwards; it lodges a small nerve, (the Vidian ;) 
it is named the hiatus Fallopii, and leads to the aqueduct of Fallopius. Farther back is a rounded eminence indicating the situa- 
tion of the superior semicircular canal. The aqueduct of Fallopius just alluded to commences at the internal auditory meatus- 
it is a small osseous tube lodged in the interior of the bone, and passing at first in an arched direction, outwards and upwards, 
then backwards and downwards towards the basis of the skull, where it ends in the stylo-mastoid foramen ; it transmits the portio 
dura, and receives, through the hiatus Fallopii, the Vidian nerve. The posterior surface looks obliquely backwards, and forms 
part of the third or posterior fossa at the base of the skull. In it will be observed a large orifice, leading to a short canal, (meatus 
auditorius internus.) The canal is oblique in its direction, having an inclination outwards and forwards. It conveys the 
auditory and facial nerves. Its fundus is formed by a lamella of bone, (lamina cribrosa,) divided into two parts by a crest or 

No. 1. The frontal process. 2. The orbital process. 3. The superior maxillary process. 4. The zygomatic process. 5. One of the 
foramina for the transmission of filaments of nerves and small arteries to the integument of the face. 

Fio. 14. An anterior view of the palate bone. 

No. 1. The horizontal portion of the palate bone. 2. Its perpendicular portion. 3. Its tuberosity. 4. The spheno-palatine foramen. 
5. The orbital portion. 6. The sphenoidal portion. 7. The ridge that gives attachment to the inferior turbinated bone. 

Fig. 15. A posterior view of the palate bone. 

No. 1. The horizontal portion. 2. The perpendicular portion. 3. The tuberosity. 4. The surface which articulates with the external 
pterygoid plate. 5. The surface which articulates with the internal pterygoid plate. 6. The ridge that gives attachment to the 
inferior turbinated bone. 7. The spheno-palatine foramen. 8. The orbital portion. 9. The sphenoidal portion. 

Fig. 16. An external view of the palate bone. 

No. 1. The perpendicular portion. 2. The posterior palatine groove. 3. The posterior palatine foramen. 4. The tuberosity. 5. The 
spheno-palatine foramen. C. The orbital portion. 7. The sphenoidal portion. 

Fig. 17. The under surface of the palate portion of the palate bone. 

No. 1. The palate spine. 2. The transverse ridge which gives attachment to the aponeurosis of the tensor palati muscle. 3. The pos- 
terior palatine foramen. 4. The tuberosity. 

Fig. 18. The vomer. 

No. 1. The broad and concave extremity, which articulates with the rostrum of the sphenoid bone. 2. The antero-superior border, 
which articulates with the central lamella of the ethmoid bone and with the cartilage of the septum. 3. The inferior border for 
articulation with the palate processes of the superior maxillary and palate bones. 4. The posterior and free border of the vomer. 



84 

ridge ; the upper or smaller part is pierced by a foramen which transmits the facial nerve, whilst the lower presents several 
very small apertures through which the fibrillae of the auditory nerve pass. About three lines further back than the orifice 
of the meatus is a narrow fissure, oblique in its direction. It is the termination of the aquaeductus vestibuli. Between the 

PLATE XIII. 

The bones of the upper and lower jaw; the teeth, the os hyoides, and the anatomical characteristics of a rib, are shown in this plate. 
Fig. 1. The two superior maxillary bones articulated: after Cheselden. 

No. 1. The body of the bone. 2. The canine fossa. 3. The infra-orbital foramen. 4. The incisive fossa. 5. The harmonial suture 
of the two bones. 6. The nasal spine. 7. The semi-lunar notch, forming the lateral boundary of the anterior nares. 8. The nasal 
process. 9. The concavity for the articulation of the lachrymal bone. 10. The malar process. 11. The tuberosity of the superior 
maxillary bone. 12. The median incisor of the right bone. 13. The lateral incisor. 14. The canine tooth. 15. The two bicus- 
pidati, or small molars. 16. The three large molars. 17, 17. The alveolar process. 18. The left superior maxillary bone. 19. 
The opening of termination of the nasal duct. 20. The opening of the antrum of Highmore. 21. The notch for the reception of the 
nasal bones. 22. The palate process of the superior maxillary bone. 

Fig. 2. The superior maxillary bone of the left side; a part of the bone has been removed in order to show the cavity of the antrum: 
after Cheselden. 

The references from 1 to 16 are the same as in the preceding figure. 17, 17. The alveolar process. 18. The cavity of the antrum 
Highmori, laid open by the removal of a part of the anterior wall of the bone. 19. The orbital process. 20. The lachrymal 
tubercle. 

Fig. 3. The left superior maxillary bone, with the pale and inferior turbinated bone ; seen upon their nasal aspect : after Cheselden. 

No. 1. The nasal surface of the superior maxillary bone. 2. The opening of the antrum. 3. The inferior turbinated bone, remaining 
attached to this surface. 4. The inferior meatus of the nose, into which the nasal duct opens. 5. The nasal process of the bone. 
6. The semi-lunar notch for the articulation of the lachrymal bone. 7. The border of the orbital plate which articulates with 
the ethmoid bone. 8. The nasal surface of the perpendicular lamella of the palate bone. 9. The nasal spine. 10, 10. The 
palate process of the superior maxillary bone. 11, 11. The alveolar process. 12, 12. The palate process of the palate bone. 13. 
The palate spine. 14. The tuberosity of the palate bone. 15. Its hamular process. 16. The groove forming part of the naso- 
palatine canal. 

Fig. 4. The inferior maxillary bone: after Cheselden. 

No. 1. The body of the bone. 2. The symphysis. 3. The mental foramen. 4, 4. The alveolar process. 5, 5. The ramus of the 
lower jaw. 6, 6. Its angle. 7, 7. The coronoid process. 8, 8. The sigmoid notch. 9. Its condyle. 10. The neck of the con- 
dyle. 11. The inferior dental foramen. 12. The mylo-hyoidean ridge. 13. The median incisors. 14. The lateral incisor. 15. 
The canine. 16. The bicuspidati or small molars. 17. Two of the large molars, the third molar or dens sapientiae has not yet 
appeared. 

Fig. 5. The inferior maxillary bone ; seen from within. 

Nos. 1, 1. The body of the bone. 2. The symphysis. 3, 3. The rough surfaces for the attachment of the digastric muscles. 4. Tu- 
bercles for the attachment of the genio-hyoidei and genio-hyo-glossi muscles. 5,5. The mylo-hyoidean ridae, at each side. 6,6. 
The smooth surface against which the sublingual gland rests. 7, 7. The surface against which the submaxillary gland rests. 8, 8. 
The ramus of the inferior maxillary bone. 9, 9. Its angle. 10, 10. The inferior dental foramen. 11, 11. The mylo-hyoidean 
groove. 12, 12. The coronoid process. 13, 13. The sigmoid notch. 14, 14. The condyle. 15, 15. The neck of the condyle. 

Fig. 6. The teeth of the upper and lower jaw : after Cheselden. 

Nos. 1,1. Median incisors. 2, 2. Lateral incisors. 3, 3. Canines. 4, 4. First bicuspidati. 5, 5. Second bicuspidati. 6, 6. First 
molars. 7, 7. Second molars. 8, 8. Third molars, or denies sapientiae. A. The second and third molars of the lower jaw closely 
locked together, and showing the recurved form of the fang which occasionally occurs. B. Section of a molar tooth, showing its 
anatomical structure. 1. The crown. 2. The neck. 3, 3. The roots or fangs. 4. The cavitas pulpa?. 

Fig. 7. The os hyoides, viewed from the front. 

No. 1. The body. 2,2. The greater cornua. 3,3. The lesser cornua. 

Fig. 8. The os hyoides, viewed upon its inner aspect. 

No. 1. The body. 2, 2. The gTeater cornua. 3, 3. The lesser cornua. 

Fig. 9. The sixth rib : after Cheselden. 

No. 11. Its shaft. 2. Its head. 3." Its neck. 4. Its tubercle. 5. The articular surface upon the tubercle. 6. The angle of the rib. 
The groove along its lower border for the lodgment of the intercostal vessels and nerve. 8. The extremity which articulates with 
the costal cartilage. 

Fig. 10. The first rib : after Cheselden. 

No. 1. Its head. 2. The, neck. 3. The tubercle. 4. The articular <siirf™ nnnr . tv, . u i - m L . 

,.,,,,,,, , .. . * ne arucular surface upon the tubercle. 5. The projection for the attachment 

of the tendon of the scalenus anticus muscle. 6. The groove for the suhplavian arte™ i tu e .u i. i ■ 

o rrn . .. c ■ i .• •, , , s ' "'« suociavian artery. 7. Ihe groove for the subclavian vein. 
8. The extremity for articulation with the costal cartilages. 

Fig. 11. Two of the dorsal vertebrae, with which a rib is articulatpd • th* fl™,™ :„ • . j j . , 

bones: after Cheselden. ' ^ ^ 1S ,lUended t0 show the mode of articulation of these 

Nos 1, !• The bodies of the vertebra, 2. The intervertebral substance. 3, 3. The transverse processes. 4. An articular process. 
5. A half facet for the head of a rib. 6. The articular surfapp nr.™ ti,o «_< <■ •_ ' *• ,m - ul<u F ul - C00 - 

.,-..„.., . , , 11,c druouldr sunace upon the extremity of the transverse process for the articulation of 
the tubercle of a rib. 7. A rib articulated wth the vertebra- a * n „.L u ir c , L • w t .u L , """cuiauon oi 
... . . ,„ ™ _ «i wiui me veneorae. ». Another half facet for the articulation of the head of a rib 9 9 

Inferior articular processes. 10. A spinous process ■«•»• •'<•'• 




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25 

aperture of the aqueduct and that of the meatus is an irregular depression, into which a small process of the dura mater 
is fixed. 

On the inferior surface of the pars petrosa, which is exceedingly irregular, we observe, proceeding from within outwards and 
backwards, a rough surface, giving attachment to the levator palati and tensor tympani muscles, the carotid foramen, the jugular 
fossa, the vaginal and styloid processes ; lastly, the stylo-mastoid foramen. The carotid foramen leads into the curved canal 
(canalis caroticus) already noticed. The jugular fossa (fossa bulbi venae jugularis interna?) is named by some the " thimble-like" 
cavity, also the " foramen lacerum posterius." It is of large size, and formed in the contiguous margins of the temporal and 
occipital bones. It is in some cases divided into two parts, but unequally, by a spicula of bone ; the anterior and inner portion 
gives passage to the glosso-pharyngeal, vagus, and spinal accessory nerves, whilst the posterior and larger one transmits the 
jugular vein. External to the margin of the fossa is the styloid or pencil-like process, long and tapering, with an inclination 
downwards and forwards. Its length varies from an inch to an inch and a half; it gives attachments to three muscles and two 
ligaments. Close before the base of the styloid process is a compressed bony plate, the free surface of which looks obliquely 
forwards and forms the back part of the glenoid or articular cavity. This is named the vaginal process, (vagina processus 
styloidei.) Between the root of the styloid process and the mastoid is the stylo-mastoid foramen, (f. stylo-mastoideum,) so 
called from its position with regard to the processes just named. It forms the outlet or termination of the aqueduct of Fallopius, 
and gives exit to the facial nerve. 

The superior border of the pars petrosa is grooved for the petrosal sinus ; the anterior, which is very short, forms, with the 
squamous part, an angle at their point of junction, in which is situated the orifice of the Eustachian tube, a canal which leads 
from the pharynx to the tympanum : above this, and separated from it by a thin horizontal lamella, (processus cochleariformis,) 
is another osseous tube, that gives passage to the tensor tympani muscle. The posterior border articulates with the basilar 
process of the occipital bone and forms with it the jugular fossa. About the middle of this edge or border is a minute foramen, 
the opening of a small canal leading from the cochlea, (aquseductus cochlese.) 

Articulations. — The temporal bone articulates with the parietal, malar, inferior maxillary, sphenoid, and occipital bones. 

Attachments of muscles. — To the zygoma is attached the masseter; to the squamous portion, the temporal; to the mastoid 
process, the retrahens aurem, the sterno-mastoid, splenius capitis, and trachello-mastoideus ; to the digastric fossa, the digastricus ; 
to the styloid process, the stylo-glossus, stylo-hyoideus, and stylo-pharyngeus ; to the apex of the petrous portion, the levator palati 
and tensor tympani. 

Developement. — The squamous, mastoid, and petrous parts of the bone have each a separate ossific centre. So have the 
processes, viz., the zygomatic, styloid, and auditory. 

The Sphenoid Bone. — The sphenoid is a single bone placed transversely at the base of the skull, and articulated with all the 
bones, of the cranium and several of those of the face, between which it is inserted somewhat like a wedge, whence its name 
[a^v, a wedge ; ^80$, like ;) its form has been likened to that of a bat with its wings extended ; and the comparison is not very 
far-fetched, particularly if the ethmoid bone remains attached, as often happens. Like other irregular bones, it maybe divided 
into body and processes. 

To place this bone in its proper position so as to perceive clearly the relations of its different parts, observe that it has two 
thick processes somewhat like legs. Hold it so that these shall project downwards, as if from beneath the body and wings, and 
let those edges of the processes which are channelled into vertical grooves look backwards. 

Of the body, or central part of the bone. — To give precision to its description, we say that it presents six aspects or surfaces, 
each of which looks in a different direction and has distinct relations : — The superior surface, which forms part of the basis of the 
skull, is of limited extent, yet is hollowed into a deep pit, which lodges the pituitary gland : hence this excavation is called pitu- 
itary fossi, and sometimes "sella Turcica," from some resemblance to a Turkish saddle, (ephippium.) On either side of the fossa 
the surface is depressed, and corresponds with the cavernous sinus ; farther back are two superficial grooves, directed from behind 
forwards, which correspond with the internal carotid arteries. Before the fossa, is a slightly depressed portion of the bone, on a 
level with the optic foramina, on which rests the commissure of the optic nerves ; — behind it is a prominent ascending lamella, of 
a square form, and sloping backwards, so as to be continuous with the basilar groove of the occipital bone : the corners of this 
lamella project over the fossa, and arc called the posterior clynoid processes, (*?ui^, a bed.) 

The inner surface is the narrow interval between the pterygoid processes; it is intersected by a prominent spine, called the 
rostrum or azygos process, which dips downwards and forwards to join the vomer. At each side are two small and slightly 
everted lamella?, (projecting from the base of the pterygoid processes,) which articulate with the margins of the vomer. Farther 
out is a small groove, which contributes with the head of the palate bone to form the pterygopalatine canal. 

The anterior surface is very irregular, and presents the openings of two deep sinuses, into which the bone is hollowed : 
these sinuses (sphenoidal) do not exist in young children; in the adult, in whom they are of considerable size, they are separated 
by a thin partition, (septum sphenoidale,) which is continuous inferiorly with the rostrum, and in the front articulates with the 
central lamella of the ethmoid bone. The sinuses are covered in anteriorly by two thin osseous plates, the sphenoidal spongy 
bones, (cornua sphenoidalia, cornets sp'henoidaux ;) these do not, however, altogether seal up the sphenoidal sinuses, but leave a 
Bones. — 4 



26 

circular aperture, by which they communicate with the posterior ethmoidal cells. In early life they are distinct, and easily 
separable ; but in the adult they become united either with the margins of the sinuses or with the ethmoid or the palate bone. 

The posterior surface is flat, and united with the basilar process of the occipital bone,— in early life by cartilage, but in adult 
age by osseous matter. 

The lateral surfaces are continuous with the great wings, which branch out from them on either side. 

Of the Processes. — The principal processes are, the great wings, the small wings, and the pterygoid processes; the minor 
ones are the ethmoid spine, processus olivaris, clinoid processes, the rostrum, the hamular and spinous processes. 

The great wings (ate majores) project outwards, forwards, and upwards, from the sides of the body of the bone, and are so 
formed as to present each three surfaces, looking in different directions; one, anterior, {orbital,) is square, smooth, inclined 
obliquely forwards, and forms part of the outer wall of the orbit; the second, (superior or cerebral,) of much greater extent, is 
elongated from behind forwards, and concave, so as to form part of the middle fossa of the basis of the skull, which supports the 
middle lobe of the brain ; the third (external or temporal) looks outwards into the temporal fossa, where it forms part of the side 
of the cranium. It is elongated from above downwards, and slightly hollowed. But it will be observed that this surface, taken 
as a whole from the top of the wing down to the root of the pterygoid process, presents two parts divided by a slight ridge ; of 
these the upper and longer one just noticed forms part of the temporal fossa, and the inferior or smaller division, of the zygo- 
matic fossa. 

The small wings, (ate minores,) called also wings of Ingrassias, are triangular in form, horizontal in direction, and extended 
forwards and outwards, on a level with the upper surface of the body — its fore part. Their upper surface, plain and flat, sup- 
ports part of the anterior cerebral lobes, the inferior one overhangs the back part of the orbit and the sphenoidal fissure. The 
anterior border, sharp, thin, and rough, articulates in the greater part of its extent with the orbital plate of the frontal bone, and 
internally, at the middle line, where the bases of the two processes are united, there is a slight angular process, {ethmoidal spine,) 
which articulates with the cribriform lamella of the ethmoid bone. The posterior border, rounded and smooth, is free and unat- 
tached, and corresponds with the fissure (fissura Sylvii) which separates the anterior from the middle lobe of the brain. The 
external and anterior ends of these processes are sharp and pointed, whilst posteriorly they terminate in two blunt tapering pro- 
ductions, which incline obliquely backwards, towards the pituitary fossa, and overlie the cavernous sinuses. These are called 
anterior clinoid processes. 

The pterygoid processes are seen at the inferior surface of the bone, from which they project down like legs rather than 
wings, though the name given to them would indicate the reverse, (rfrtpvi, a wing.) Each of these consists of two narrow plates, 
{pterygoid lamellae,) united at an angle in front, and diverging behind, so as to form an angular groove, {pterygoid fossa.) The 
internal plate, longer and narrower than the external, is prolonged into a slight round process, named, from its crooked form, the 
hook-like or hamular process, round which plays the tendon of the tensor palati muscle. The external lamella looks outwards, 
and somewhat forwards, bounds the zygomatic fossa, and gives attachment to the external pterygoid muscle. At the root of the 
internal lamella is situated a slight depression, {fossa navicularis,) which gives attachment to the tensor palati muscle ; in the 
groove or fossa, between the two plates, arises the internal pterygoid muscle. The groove is incomplete at its lower part when 
the sphenoid bone is examined by itself; for an^angular interstice exists between the pterygoid lamelte. This, however, is filled 
up by a part of the pyramidal process of the palate bone, which is inserted between the margins of the lamelte. 

The ethmoid spine, already noticed, is a very small angular plate, which projects forward on a level with the upper surface 
of the lesser wings in the middle line, and articulates with the cribriform lamella of the ethmoid bone. 

The processus olivaris is a minute elevation seen on that depressed piece of bone on a level with the optic foramina, and 
which supports the commissure of the optic nerves. 

The clinoid processes are two pair, one before, the other behind the pituitary fossa ; therefore called anterior and posterior. 
A spicula of bone often passes from the anterior to the posterior clinoid process at one or both sides ; and occasionally one dips 
down from this to the body of the bone. 

The rostrum is the prominent angular ridge, which projects downwards from the under or guttural surface of the bone, 
dividing it into two parts. 

The hamular processes projects from the termination of the internal pterygoid plate, is thin, constricted, and curved in the 
greater part of its extent, but ends in a small blunted tubercle. 

The spinous process are placed at the posterior and inner terminations of the great wings, from which they project down- 
wards about two lines. 

Each lateral half of the bone presents a fissure, four foramina, and a canal. The fissure, {fissura sphenoidalis,) triangular 
and elongated, is placed between the lesser and greater wings, opens into the orbit, (hence sometimes named foramen lacerum 
orbitale,) and transmits the third, the fourth, and the sixth nerves, the ophthalmic branch of the fifth and the ophthalmic vein. 
This fissure ,s separated at its base from the foramen op.icum by a narrow plate of bone which passes from the under surface of 
the anterior chnoid process (at its root) obliquely down to the body of the sphenoid bone; to this is attached a. small tendon, 
common to the inferior, internal, and external recti muscles of the eye. Of the foramina,_the optic foramen inclines outwards 



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27 

and forwards on a level with the fore-part of the body of the bone ; it transmits the optic nerve and the ophthalmic artery. 
Farther back and on a lower plane, inasmuch as it is situated in the great wing, is a round aperture, leading forwards ; it is the 
foramen rotundum, which transmits the superior maxillary branch of the fifth pair of nerves: a little farther back and more 
external is a larger foramen, of an oval form, hence called foramen ovale; it gives passage to the inferior maxillary branch : 
near the posterior angle of the ala is the foramen spinosum ; it is very small, and transmits the middle meningeal artery. The 
root, or base, of each internal pterygoid process is pierced by a circular foramen, (pterygoideum,) more properly a canal, extend- 
ing horizontally from before backwards, slightly expanded before, narrowed behind, and giving passage to the posterior branch 
from Meckel's ganglion, ( Vidian, pterygoid.) 

Articulations. — The body of the sphenoid bone articulates posteriorly with the basilar process of the occipital, anteriorly with 
the ethmoid ; with the orbital processes of the frontal by the lesser and greater ala? ; with the anterior inferior angles of both 
parietal, and the squamous portion of the two temporal, by the great alae, and by the spinous processes with the angles between 
the petrous and squamous portions of that bone : with the vomer it articulates by the rostrum ; with the malar bones by means 
of the external border of the orbital plates, and with the palate bones by the pterygoid processes ; — in all, twelve bones. 

Attachments of muscles. — Round the optic foramen in each orbit are attached the four recti, the obliquus superior, and 
levator palpebral muscles ; to the external surface of the great ala at each side, the temporal muscle ; to the external pterygoid 
process, the external pterygoid muscle ; to the pterygoid fossa, the internal pterygoid ; to the inferior half of the internal pterygoid 
plate, the superior constrictor of the pharynx; and to the fossa navicularis, the circumflexus palati; and to the spinous process, 
the laxator tympani. 

Developement. — There are two osseous centres in the great wings, two in the pterygoid processes, and two in the small 
wings. The anterior and posterior segments of the body of the bone commence by distinct points; and as these in some instances 
unite, one with the great wings and the other with the small ones, before they become joined to one another, this condition of the 
bone presents an analogy with its permanent state in fishes, reptiles, and most mammalia, in which we find an anterior and pos- 
terior sphenoid bone. There appear also two osseous points at the inner borders of the optic foramina. 

Ethmoid Bone. — The ethmoid, or sieve-shaped bone, {^ep.o^, a sieve ; u§ ;, like ; os ethmoides,) is common to the cranium, 
the orbits, and the nasal fossae ; it is placed at the fore part of the base of the skull, from which it projects downwards, and is 
inserted between the orbital plates of the frontal bone, lying behind the nasal and superior maxillary bones, before the sphenoid 
and above the vomer. It is exceedingly light and thin, considering its size ; and seems, at first, but a collection of irregular cells, 
enclosed between plates of bone as thin as paper. It is of a cuboid figure, symmetrical, and composed of two lateral masses, 
between which is interposed a central vertical plate. This points out a mode of dividing the bone for the purpose of description, 
but it is more convenient to consider it as a whole, and examine separately each of its six surfaces. 

To place the bone in its proper position, observe that its upper surface is the one from which arises a smooth angular process 
like a cock's comb. The short border of this looks forward, and the long sloping one backwards. 

The superior, or cerebral surface of the bone, is at once recognised by its presenting a triangular process, which projects 
upwards from it, in the middle line ; this process, from some resemblance to a cock's comb, is called crista galli. The surface 
of the crista is smooth and compact, its form triangular, the base being horizontal, and on a level with the cribriform plate, below 
which it is continuous with the perpendicular lamella forming the septum narium ; the posterior border of this process is long, 
and slopes backwards, but the anterior is short, and nearly perpendicular; at its junction with the base two small bony masses 
sometimes project forwards, leaving between them a fissure which forms part of the " foramen caecum," placed in the middle line 
at the junction of this bone with the frontal. The crista galli is usually perpendicular, but occasionally inclines to one side ; it is 

PLATE XIV. 

An anterior view of the trunk of the skeleton : after Cheselden. 

No. 1. The axis. 2. Its odontoid process. 3, 3. The foramen in its transverse process for the passage of the vertebral artery. 4, 4. 
The bodies of the cervical vertebrae. 5, 5. Their intervertebral substance. <3, G. The transverse processes, with their anterior and 
posterior tubercles. 7. The body of the first dorsal vertebra. 8, 8. The first rib. 9, 9. The head of the first rib, which in this 
subject would seem to articulate with the last cervical vertebra. 10, 10. The clavicle. 11, 11. Its rounded or sternal extremity. 
12, 12. Its flattened or scapular end. 13, 13. The anterior surface of the scapula. 14, 14, Its superior or short border. 15, 15. 
Its posterior border or base. 16, 16. Its anterior border. 17, 17. Glenoid cavity. 18, 18. The neck of the scapula. 19, 19. The 
coracoid process. 20, 20. The acromion process. 21,21. The seven true ribs. 22, 22. The false ribs. 23, 23. The two floating 
ribs. 24, 24. The costal ca»tilages. 25. The first piece of the sternum. 20. The middle piece. 27. The ensiform cartilage! 
28. The last dorsal vertebra. 29, 29. The bodies of the five lumbar vertebrae. 30, 30. Their transverse processes. 31. The 
sacrum. 32. The coccyx. 33, 33. The os ilium. 34, 31. Its crest. 35, 35. The anterior and superior spinous process. 3G, 30. 
The anterior inferior spinous process. 37. The acetabulum of the right side. 38,38. The body of the os pubis. 39,39. Its crest. 
40,40. The ilio-pectineal eminence. 41. The symphysis pubis. 12,42. The ramus of the pubis at each Bide. 13, 43. The 
ramus of the ischium. 44. The tuberosity of the ischium. 45. The spine of the ischium. 10. The great sacro-ischiatic notch. 
47, 47. The obturator foramen. 



28 

sometimes bulged a little at the sides, and is then found to enclose a small sinus; it gives attachment to the falx cerebri, the two 
layers of which in a manner embrace it. 

Beside and behind the crista is the sieve-like or cribriform lamella, (lamella cribrosa.) It consists of a narrow plate of bone, 
pierced by a number of holes, from which it derives its name ; posteriorly this plate of bone is, for a very little way, even and 
horizontal ; it then becomes depressed into two grooves, beside the crista, which lodge the ganglia of the olfactory nerves. This 
part of the surface is narrow, elongated from behind forwards, and pierced by numerous foramina, for the transmission of the 
filaments of the olfactory nerves. The foramina in it are of three sorts : those which lie along the middle of the groove are mere 
holes or perforations which permit the filaments of the nerves, with their membranous investments, to pass down to the roof of 
the nares ; the external and internal rows are larger, and form the orifices of small canals, which are grooved in the bone, and 
subdivide as they descend into the septum and spongy bones. In the anterior border of the cribriform lamella, and close to the 
crista galli, is a fissure at each side of its base, which transmits the nasal filament of the ophthalmic nerve. Along the outer 
margin of the cribriform plate we observe several small cellules, which are open, and, as it were, incomplete when the bone is 
detached from its natural situation, but are closed in by the orbital plates of the frontal bone, and completed by a junction with 
the cells observed in their border. At the posterior margin of this surface, and in the middle line, is a slight notch, which receives 
the ethmoid spine of the sphenoid bone. 

The anterior surface of the bone presents in the middle the edge of the perpendicular or nasal lamella ; at the sides of this 
are narrow grooves which separate it from the lateral masses, and form the upper part of the nasal fossae ; still farther out are 
some open cellules, which when the bone is in its place are closed by the ascending process of the superior maxillary bone. 

The posterior surffce presents also in the middle the edge of the perpendicular lamella, then the grooved posterior margins 
of the ethmoidal turbinate bones, and still more externally large open cellules which are closed by the sphenoid bone and its tur- 
binate bones, and lower down by the head of the palate hones. 

The lateral or orbital surfaces are smooth and plain; each is formed of a thin plate of bone, (lamella plana, os planum,) 
which lies in the inner wall of the orbits. 

Thus far we can proceed with our description of the bone as if it were a single piece, which presented several aspects, each 
requiring to be noticed ; but when we look at it from below we find it expedient to consider it as divisible into a central or median 
plate, and two lateral parts or masses. 

The inferior, or nasal surface of the bone, is of considerable extent, and presents in the middle line a fiat plate of bone, and 
two lateral masses separated from it by a narrow interval : these lateral parts are formed of thin plates, enclosing cellules, which 
appear so complex as to be likened by some persons to a labyrinth. The descending or nasal plate, (lamella nasalis,) called also 
the perpendicular plate, though it frequently inclines to one side, forms a considerable part of the septum nasi ; it is continuous 
above with the base of the crista galli, as already stated ; below, it articulates with the vomer and the triangular cartilage of the 
nose ; its anterior margin joins by its upper part with the nasal process of the frontal bone, and lower down supports the ossa 
nasi ; the posterior margin articulates with the septum sphenoidale. This plate presents a number of grooves and minute canals, 
leading from the foramina of the cribriform lamella, for the transmission of the olfactory nerves : in the natural condition it is 
covered by the pituitary membrane. 

Lateral masses. — The external surface of each of these consists of a thin, smooth, and nearly vertical plate of bone, (lamella 
plana, os planum,) which closes in the ethmoidal cells, and forms a considerable part of the inner wall of the orbit : it articulates 
above with the orbital plate of the frontal bone ; below, with the superior maxilla and palate bone ; in front, with the os unguis ; 
and behind, with the sphenoid. At its anterior and posterior margins, the ethmoidal cells are open when the bone is detached 

PLATE XV. 

A posterior view of the trunk of the skeleton : after Cheselden. 

No. 1. The last cervical vertebra. 2. The first dorsal vertebra. 3,3. The spinous processes of the dorsal vertebrae, showing their 
imbricated position. 4, -1. The two last dorsal vertebrae, showing their approximation in form to the lumbar vertebra and their 
exceedingly short transverse processes. 5. The first lumbar vertebra. 6. The last lumbar vertebra. 7, 7. The bodies of the 
lumbar vertebra. 8, 8. The sacrum. 9. The first piece of the coccyx. 10, 10. The posterior sacral foramina. 11. The termina- 
tion of the sacral canal. 12, 12. The spaces between the arches of the vertebra, which are closed in the fresh subject by the 
hgamenta subflava. 13, 13. The first rib. 14, 11. The seventh and last true rib. 15, 15. The three upper false ribs. 16, 16. The 
two last false r,bs,-the floating ribs. 17, 17. The costal cartilages. lg. The first piece of the sternum. 19, 19. The sternum. 
20. The ensiform cartilage. 21, 21. The tubercles of the ribs articulating with the extremities of the transverse processes of the 
ten upper dorsal vertebra. 22, 22. The angles of the ribs; the surface between the tubercles and the angles is rough for the 
attachment ot muscles. 23, 23. The inter-vertebral substance, situated between the vertebra. 21. The ilium. 25, 25. Its crest. 
26. The posterior superior spinous process. 27. The posterior inferior spinous process. 28. The anterior inferior spinous process. 
29. The border of the acetabulum. 30. The great sacro-ischiatic notch. 31, 31. The ischium. 32. The spine of the ischium. 
33. The lesser sacro-ischiatic notch. 34. The tuberosity of the ischium. 35. The ramus of the ischium. 3ti. The os pubis. 
37. Its ramus. 38. The symphysis pubis. 39,39. The ilio-pectineal line. 40. The obturator foramen. 




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29 

from its connexions ; in the former situation they are closed by the os unguis ; in the latter by the sphenoid spongy bones. In its 
upper margin are two grooves, which are formed into foramina by similar indentations in the frontal bones, and so form the 
internal orbital foramina, {foramen orbitarium internum, anterius et poster ius.) 

The inner surface of each lateral mass forms part of the external wall of the corresponding nasal fossa, and consists of a thin 
osseous plate, connected above with the cribriform lamella, from which it hangs down, and below ends in a free margin, which is 
convoluted a little, and represents the middle spongy bone. At its upper and fore part is a square, flat, but rough surface, which 
is pierced by a number of grooves, leading from the foramina of the cribriform lamella; posteriorly are placed two thin and also 
rough osseous plates, curved a little, so as to represent small bivalve shells, from which circumstance they are called ethmoidal 
turbinate bones ; but from their texture, being cellular and porous on the surface, they are named spongy bones. Of these, the 
first or upper one, (concha superior,) which is also placed farther back, is very small ; by the curve or coil which it makes it arches 
over, and forms a groove or channel, [meatus naris superior:) this is of small extent from before backwards, not being more than 
half that of the ethmoid bone ; it communicates with the posterior ethmoidal cells, and the sphenoidal sinuses. Still lower down 
is another osseous lamella, thin, rough, and convoluted, which is the second ethmoidal spongy or turbinate bone. Its lower 
margin is more rough and prominent than that of the upper one, and its extent from before backwards nearly double. Beneath 
this is a groove or channel which it overhangs so as to form the second meatus naris, which communicates with the anterior 
ethmoidal cells and the frontal sinuses. 

The osseous rough plate here described gives attachment by its outer surface to a number of osseous lamella), thin and 
delicate, which pass across the space between it and the lamella plana, dividing it into a number of cells, {ethmoidal.) These do 
not all communicate : they are separated into two sets by a sort of transverse partition, the posterior being small and few in 
number — from four to five, — whilst the anterior, larger and more numerous, communicate with the frontal sinus. The cellule, 
which directly communicates with the middle meatus, is prolonged, in a curved direction, upwards and forwards, opening by a 
small aperture into the anterior ethmoidal cells, and by another, farther on, into the frontal sinus; and, as it is broad below and 
tapering above, it assumes somewhat the form of a funnel, and hence is named infundibulum. 

The superior border of each lateral mass presents some incomplete cells, before noticed, when describing the cribriform 
plate; the inferior gives off some irregular lamella;, which articulate with the side of the maxillary sinus and the inferior turbinate 
bone ; the anterior also exhibits some incomplete cells, which are closed in by the os unguis and the nasal process of the superior 
maxillary bone. 

Articulations. — The ethmoid articulates with thirteen bones — the frontal, the sphenoid, and vomer, two nasal, two ossa 
unguis, two superior maxillary, two palatal, and two inferior spongy bones. 

Developement. — There is an ossific centre in each lateral mass, and one in the perpendicular lamella. 

Ossa triquetra. — Accidental, or supernumerary bones, are not nnfrequently found in skulls. From their form, which is 
very variable, they are sometimes called triquetra, at others, triangularia, or ossa Wormii, from Wormius the anatomist, who is 
said to have given the first detailed description of them. They are osseous plates, with serrated margins, inserted, as it were, 
between two cranial bones, and appearing like islets placed in the sutures. Their most ordinary position is in the lambdoid suture, 
next in the sagittal, seldom if ever in the coronal, never in the squamous. The superior angle of the occipital bone sometimes 
occurs as an accessory piece; so does the anterior inferior angle of the parietal. They are not found before the sixth or eighth 
month after birth ; and, whatever varieties of size and appearance they may present, the principle of their formation is the same 
in all cases. As the broad bones grow by successive deposits, extending from their central points towards the margins, whenever 
the natural process is retarded or interrupted, the mode of osseous deposition takes a new direction, a new centre is established 
in the layer of cartilage between the margins of the bones, and therefore in the situation of the suture, from which it extends 
outwards until it comes into contact with the margins of the contiguous bones, with which it becomes united in the usual way by 
suture. 

Bones of the face. — The bones of the face are fourteen in number. 

The superior maxillary bone.— This bone (maxilla superior) is very irregular ; it presents an external convex surface, cor- 
responding with the anterior and lateral parts of the face; another, internal, of considerable extent, corresponding with the nasal 
cavity ; one, superior, smooth, and inclined inwards, forming the floor of the orbit, and surmounted internally by a triangular 
process, forming the side of the nose ; lastly, a surface which projects horizontally inwards, to form the arch of the palate. The 
external surface is bounded inferiorly by a thick dependent border, (alveola,) for the lodgment of the teeth ; to this, as to a common 
point of union, all the other parts of the bone may be referred. 

The alveolar border, thick, semicircular, convex externally, concave internally, is pierced along its margin by a number of 
deep pits, {alveoli,) into which the teeth are inserted. The pits or sockets vary in form and depth, conforming in these particulars 
to the roots of the teeth which they receive. From this border the external side ascends upwards to the margin of the orbit, 
presenting some depressions and elevations; but at its fore part it is interrupted and excavated so as to present a dimply concave 
margin, which, with a similar one in the corresponding bone, forms the anterior nares. This excavation is surmounted by a 
process, {ascending or nasal.) prolonged as far as the frontal bone, with which it articulates. The external surface of this process, 



30 

slightly grooved, gives attachment to the orbicularis palpebrarum muscle and the levator labii superioris absque nasi. The 
internal, or nasal surface, somewhat concave, presents a rough line, running from before backwards, winch articulates with the 
inferior spongy bone ; above this is a depression corresponding with the middle meatus of the nose, and, towards the summit, a 
rough surface, which closes in the anterior ethmoidal cells. The anterior border is rough, for its attachment to the nasal bone; 
the posterior presents a well-marked groove, running from above downwards, and a little backwards with a slight curve, and 
which is completed into a canal by a similar one in the os unguis, for the lachrymal sac. 

The part of the external surface a little above the molar teeth is elevated into a rough projection, (malar eminence,) for its 
articulation with the malar bone. Anterior and inferior to this is observed a fossa, (fossa canina,) which gives attachment to the 
levator angnli oris. Between this fossa and the margin of the orbit is the infra-orbital foramen, which transmits the superior 
maxillary nerve. A little above the sockets of the incisor teeth is a slight depression, (myrtiform fossa,) which gives attachment 

PLATE XVI. 

The clavicle and scapula, with the ligaments of the sterno-clavicular articulation and shoulder joint. 

Fig. 1. The clavicle of the left side of the skeleton. 

No. 1. The sternal extremity. 2. Its articulating surface. 3. Its scapular end. 4. The surface which articulates with the acromion 
process. 

Fig. 2. The under surface of the same clavicle. 

No. 1. The surface which articulates with the sternum. 2. The rough surface for the attachment of the rhomboid ligament. 3, 3. The 
grooved surface for lodging the subclavius muscle. 4. The rough surface for the attachment of the coraco-clavicular ligament. 
5. The scapular end of the clavicle. 

Fig. 3. The scapula of the left side; its dorsal aspect. 

No. 1. The superior border of the scapula. 2. The superior angle of the scapula. 3, 3. Its posterior border. 4, 4. The spine. 5. The 
triangular smooth surface at the commencement of the spine, over which the trapezius glides upon a bursa. C. The acromion 
process. 7. The suprn-spinatus fossa. 8. The infra-spinatus fossa. 9. The neck of the scapula. 10. The glenoid fossa. 11. The 
apex of the glenoid fossa, to which the long tendon of the biceps is attached. 12. The coracoid process. 13. The anterior or 
inferior border of the scapula. 11. The rough surface from which the middle head of the triceps muscle arises. 15. The surface 
for the attachment of the teres minor muscle. 16. The surface for the attachment of the teres major muscle. 17. The inferior angle 
of the scapula. 

Fig. 4. The anterior surface of the scapula of the left side. 

No. 1. The superior border of the scapula. 2. The supra-scapular notch. 3. The superior angle of the bone. 4, 4. Its posterior 
border. 5. The inferior angle. 6, 6. The anterior or inferior border. 7, 7. The concave surface of the venter of the scapula. 
8. The neck of the scapula. 9. Its glenoid cavity. 10. The rough ridge which gives attachment to the long head of the triceps 
muscle. 11. The coracoid process. 12. The acromion process. 13. The smooth surface which articulates with the scapular end 
of the clavicle. 14. The spine of the scapula. 

Fig. 5. An anterior view of the sterno-clavicular and costo-sternal articulations. 

Nos. 1,1. The sternal extremities of the clavicles. 2, 2. The anterior sterno-clavicular ligaments. 3. The interclavicular ligament. 
1, 4. The costo-clavicular or rhomboid ligaments. 5, 5. The first rib at each side. 6, 6. The costal cartilages of the second and 
third ribs. 7, 7. Anterior costo-sternal ligaments. 

Fig. 6. A posterior view of the sterno-clavicular and costo-sternal articulations. 

Nos. 1,1. The posterior sterno-clavicular ligaments. 2. The inter-clavicular ligament. 3, 3. The costo-clavicular or rhomboid 
ligaments. 4, 1. The posterior costo-sternal ligaments. 5, 5. The superior costo-sternal ligaments. 6, 6. The inferior costo- 
sternal ligaments. 

Fig. 7. An anterior view of the ligaments of the shoulder joint. 

No. 1. A part of the scapula. 2. The upper part of the humerus. 3. A part of the scapular end of the clavicle. 4. The scapulo- 
clavicular articulation. 5. Its inferior ligament. 6. The coracoid process. 7. The coraco-clavicular or trapezoid ligament. 8. The 
under surface of the acromion process. 9. The coraco-acromial ligament. 1 0. The transverse or coracoid ligament, converting the 
supra-scapular notch into a foramen. 11. The capsular ligament of the shoulder joint. 12. The coraco-humeral liaament. 13. The 
tendon of the sub-scapulans muscle. 14. The tendon of the long head of the biceps, escaping from the shoulder°joint. 

Fig. 8. A posterior view of the shoulder joint. 

No. 1. The spine of the scapula. 2. Its acromion process. 3. The scapular extremity of the clavicle. 4. The superior scapuloclavi- 
cular ligament. 5. The coracoid process. 6. The coraco-clavicular ligament, or conoid ligament. 7. The transverse or coracoid 
ligament crossing the supra-scapular notch. 8. The supra-scapular foramen. 9. The superior border of the scapula. 10. The 
coraco-acromial hgament. 11. The capsular ligament of the shoulder joint. 12. The tendon of the supra-spinatus muscle. 13. The 
tendon of the infra-spinatus. 14. The tendon of the teres minor. 15. The neck of the humerus. 

Fig. 9. A portion of the scapula, showing the glenoid cavity and ligament. 

No. 1. The acromion process. 2. The coracoid process. 3. The glenoid cavity. 4, 4. The glenoid ligament. 5. The tendon of the 
long head of the biceps. 

Fig. 10. A section of the shoulder joint, showing the interior of its cavity. 

No.l. The anterior surface of the scapula. 2. The head of the humerus. * 3. Part of the glenoid cavity, i, 1. The cu t border of the 
capsular hgament. 5. The tendon of the long head of the biceps, passing through the cavity of the joint. 0. P art of the 
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to the depressor muscle of the ala of the nose. Behind the malar tuberosity the surface is slightly excavated, and forms part of 
the zygomatic fossa; towards the posterior border it is plain, and forms one side of the spheno-maxillary fissure; and, at its 
junction with the orbital plate, it is rounded off and leads to the entrance of the infra-orbital canal. This surface is pierced by a 
number of foramina, which transmit the superior dental nerves ; it terminates by a slight tuberosity, which projects behind the 
last molar tooth. The inner surface of its posterior border is rough, for its attachment to the tuberosity of the palate bone, and 
presents also a slight groove, contributing to the formation of the posterior palatine canal, which transmits the descending palatine 
branches from Meckel's ganglion. 

From the upper border of the external surface, the orbital plate projects inwards, forming the floor of the orbit ; its surface 
is smooth, being merely interrupted by the groove which leads to the infra-orbital canal ; and at its inner and fore part near the 
lachrymal groove is a minute depression, which gives origin to the inferior oblique muscle of the eye. 

The horizontal or palate plate of the bone projects inwards, forming the roof of the mouth, and the floor of the nares. Its 
nasal surface is concave from side to side, and smooth ; externally it is continuous with the body of the bone, internally it presents 
a rough surface, which is articulated with the corresponding bone, and surmounted by a ridge, which completes the septum 
narium by articulating with the vomer and nasal cartilage ; in front it is prolonged a little, so as to form a small process, (anterior 
nasal spine ;) beside it is the foramen, leading into the anterior palatine canal, which lodges the naso-palatine ganglion. The 
inferior surface of the palate plate is rough, arched, and overhangs the mouth. 

The body of the bone is hollowed into a large cavity, antrum Highmori, or maxillare, which in the fresh state is lined by 
mucous membrane and communicates with the middle meatus of the nose. Its orifice appears of great size in the dried bone 
when detached from its connexions, but it is considerably diminished when the contiguous bones are in their natural position, viz. 
the ethmoid, the inferior turbinate, and the palatal. 

Articulations. — With the corresponding bone ; with the frontal, by its nasal process ; also with the ethmoid and os nasi ; 
with the palate bone ; with the malar, by the malar eminence ; with the os unguis, the vomer, the inferior spongy bone, and the 
nasal cartilage. 

Attachments of muscles. — Proceeding from below upwards ; — above the border of the alveolar arch, the buccinator, and the 
depressor labii superioris aleeque nasi ; to the canine fossa, the levator anguli oris, and the compressor nasi ; to the margin of the 
orbit, part of the levator labii superioris ; to the nasal process, the orbicularis palpebrarum, and the common elevator of the lip 
and ala of the nose ; and just within the orbit, the inferior oblique muscle of the eye. 

Developement. — In this case there are several ossific centres, — one in the nasal process, one in the orbital, one in the body, 
and one or two in the palate process. If the growth be interrupted, the fore part of the alveolar border with a portion of the 
palatal arch may remain separate from the rest of the bone, and represent an inter-maxillary bone. 

The Malar Bone. — The malar bone, (os malse,) common to the face and orbit, forms the most prominent point of the side 
of the former, and the greater part of the outer border of the latter. Its form is quadrangular. The facial or anterior surface, 
pierced by some foramina for small vessels, is convex, and gives attachment to the zygomatic muscles ; — the posterior overlays 
the zygomatic fossa, and is rough at its fore part for its articulation with the superior maxillary bone. The superior surface 
smooth, narrow, and lunated, extends into the orbit, and articulates with the frontal, sphenoid, and superior maxillary bones. 

The superior border forms the outer margin of the orbit ; the inferior is on a line with the zygomatic arch, which it con- 
tributes to form ; the anterior articulates with the maxillary bone ; the posterior, curved, gives attachment to the temporal 
aponeurosis. 

Articulations. — It articulates with the frontal, superior maxillary, temporal, and sphenoid bones. 

Attachments of muscles. — The zygomatici, to its anterior surface ; the masseter, to its inferior border ; to its anterior an°Ie 
part of the levator labii superioris. 

Developement. — It grows from a single ossific point. 

The Nasal Bones. — The nasal bones, (ossa nasi,) situated beneath the frontal bone, and between the ascending processes of 
the superior maxillary, are small, and irregularly quadrilateral, and form what is called the "bridge" of the nose. They are 
thick and narrow in their upper part, but gradually become wider and thinner lower down. The anterior surface of each, con- 
cave from above downwards, convex from side to side, presents a minute vascular foramen ; the posterior, or nasal, is marked by 
the passage of a branch of the nasal nerve ; the superior border articulates with the frontal bone ; the inferior with the nasal 
cartilage ; the external with the ascending process of the maxillary bone ; the internal with its fellow of the opposite side, and is 
supported by the nasal spine of the frontal bone, and the perpendicular plate of the ethmoid. 

They give attachment to the pyramidales and compressores nasi ; and are developed each from a single osseous centre. 
Os Unguis — Os Lachrymale. — This small bone is named "ungual" from a resemblance, if not in form, at least in thinness 
and size, to a finger-nail, (unguis;) it is also called the "lachrymal" bone, from its presenting a groove which, with a similar exca- 
vation in the nasal process of the superior maxilla, forms the lachrymal groove. Placed at the inner and anterior part of the 
orbit, it presents two surfaces and four borders; its external or orbital surface, plain in the greater part of its extent, is hollowed 
anteriorly by a groove which runs from above downwards, and contributes, as above stated, to lodge the lachrymal sac. Part of the 



32 

internal surface, which is rough, corresponds with the anterior ethmoidal cells, the rest with the middle meatus narium. The 
superior border is articulated with the orbital process of the frontal bone ; the inferior with the superior maxillary bone ; and 
where it dips down, to form a part of the lachrymal canal, it joins the inferior spongy bone ; anteriorly, it rests on the nasal pro- 
cesses of the superior maxillary bone, and posteriorly on the os planum of the ethmoid. 

It is developed from one osseous centre. 

The Palate Bone.— The palate bone, (os palati,) wedged in between the superior maxillary and sphenoid bones, is common 
to the cavity of the mouth, nares, and orbit. In its form this bone somewhat resembles that of the letter L, one part being 
horizontal, the other vertical. 

The horizontal or palate plate of the bone, which is nearly square, and forms the back part of the roof of the mouth and 
of the floor of the nares, articulates anteriorly with the palate plate of the maxillary bone ; internally, it presents a rough thick 
border which rises up into a ridge, which joins with its fellow of the opposite side, and with it forms a groove which receives 
the lower border of the vomer; externally it unites at right angles with the vertical portion of the bone; posteriorly it presents 
a thin free border, forming the limit of the hard palate, and giving attachment to the velum or soft palate which projects down- 
wards from it; it is slightly concave, and has at the inner angle a pointed process, (the palate spine.) The superior surface of 
this plate or process is smooth, and forms the back part of the floor of the nasal cavity : the inferior, which forms part of the roof 

PLATE XVII. 

The bones of the upper extremity. 

Fig. 1. The bones of the left upper extremity, in their natural relations: after Cheselden. 

No. 1. The anterior surface or venter of the scapula. 2. Its superior angle. 3. Its inferior angle. 4. The posterior border of the 
same bone. 5. Its anterior or inferior border. 6. The superior border. 7. The supra-scapular notch. 8. The neck of the. scapula. 
9. The coracoid process. 10. A part of the spine of the scapula. 11. The clavicle articulated with the acromion process of the 
scapula. 12. Its sternal end. 13. The shaft of the humerus. 14. The head of the humerus. 15. Its neck. 16. Its surgical 
neck. 17. The lesser tuberosity of the humerus. 18. The internal condyle. 19. The shaft of the ulna. 20. The olecranon 
process. 21. The coronoid process. 22. The interosseous ridge of the ulna. 23. Its styloid process. 24. The radius. 25. Its 
head. 26. Its tuberosity. 27. Its interosseous ridge. 28. The styloid process of the radius. 29. The scaphoid bone of the 
carpus. 30. The semi-lunar bone. 31. The cuneiform bone. 32. The pisiform bone. 33. The trapezium. 34. The trapezoides. 
35. The os magnum. 36. The unciform bone. 37, 37. The metacarpal bones. 38, 38. The first row of phalanges. 39, 39. The 
second row of phalanges. 40, 40. The third or last phalanges. 41. The neck of the radius. 

Fig. 2. A posterior view of the bones of the left upper extremity, in their natural relations. 

No. 1. The dorsum of the scapula; its infra-spinous fossa;. 2. The supra-spinous fossa. 3. The spine of the scapula. 4. The smooth 
surface at the commencement of the spine, over which the tendon of the trapezius muscle plays. 5. The acromion process; arti- 
culating, by its extremity, with the clavicle. 6. The clavicle. 7. Its sternal end. 8. The base of the coracoid process. 9'. The 
apex of the coracoid process. 10. The superior border of the scapula. 11. The supra-scapular notch. 12. The superior angle of 
the bone. 13. Its inferior angle. 14, 14. Its posterior border. 15. Its anterior border. 16. The shaft of the humerus. 17. The 
rough eminence for the attachment of the tendon of the deltoid muscle. 18. The bicipital groove, upon the head of the bone. 
19. The greater tuberosity of the humerus. 20. The lesser tuberosity. 21. The trochlea of the humerus. 22. The internal con- 
dyle. 23. The rounded articular surface for articulation with the head of the radius. 24. The external condyle. 25. The depres- 
sion for the reception of the coronoid process of the ulna, during flexion of the foramen. 26. The radius 27 The grooves on 
the posterior surface of the lower extremity of the radius, for the passage of the extensor tendons to the back of the hand. 28. The 
ulna. 29^ Its coronoid process. 30 The lower extremity of the ulna. 31. Its styloid process. 32. The scaphoid bone of the 
carpus. 33. The semi-lunar bone 34 The trapez.um. 35. The trapezoides. 36. The os magnum. 37. The unciform bone. 

I ig. 3. A posterior view of the bones of the left upper extremity of a fcetus : after Cheselden 

No. 1 The scapula. 2, 2. The rim of cartilage which completes the posterior border of the" scapula. 3. The spine of the scapula. 
. Phe acromion .process, which , S as yet cartilage. 5. The cartilaginous coracoid process. 6. The cartilaginous head of the 
humerus. 7. The cartilaginous lower extremity of the humerus 8 ThP n ,lii,. . J 1 u- u V • , , 

mitip* Th» h™ = J f^ ~ u- a •, " 1Baumerus - 8 - l ne radius and ulna, which are cartilaginous at both extre- 

mities. J. 1 he bones ot the carpus, chiefly cartilaginous. 

Fig. 4. A foetal clavicle, cartilaginous at both extremities. 

Fig. 5. Section of an adult clavicle, showing its cancellous structure: after Cheselden. 

Fig. 6. A scapula, seen upon its anterior and external aspect. 

No. K The glenoid cavity. 2. The rough surface for the attachment of the loner tendon of the hicen. S Th -a 

The spine of the scapula. 5. The acromion process fi TV, A 1 ° f, P The coracold P rocess ' 4< 

surface on the anterior border of the bonTfor the a tachme^t of t, T 7? °/ f ^ ?> ItS ^^ «■* 8 " The ™* 
teres minor muscle. l . The surface of *£^^£^^ «*? ??* f" "cc of attachment of the 

Fig. 7. The scapula, seen upon its superior aspect. J ^ lnf<m0r a " gle ° f the bone - 

No. 1. The supra-spinous fossa. 2. The spine of the seanul-, «? ru u 

tendon of the trapezius muscle. 4. The acromion proce s' 5* Th T , * * ** commencement °' the spine for the 

scapular notch. 8. The superior border of the scapul 9 Thl , ^ , T^ * The c - acoid P—ss. 7. The supra- 

F.g. 8. A fetal scapula, showing the process of ossificatmn : IJcllZZ ^ *" ^ ^ A ^ * ^ ^^ ^ 

No. 1. The venter of the scapula. 2.2 Thp rim nf n„.;i,„ e 

cess. 4. The coracoid process osseou i t h cl , n form,n ^ ts P ost «»or border and inferior angle. 3. The acromion pro 

process, osseous in the centre, cartilaginous at both extremities. 5. The cartilaginous head of the scapula. 



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33 

of the mouth, is unequal, and marked by a transverse ridge, into which the tendinous fibres of the circumflexus palati muscle are 
inserted ; it presents also an oval foramen, being the inferior termination of the posterior palatine canal, which transmits the large 
descending palatine nerve and accompanying vessels ; and farther back, another of smaller size, which transmits the middle 
palatine nerve. 

At the junction of the horizontal and vertical portions, is situated a thick, rough tubercle, {tuberosity , pyramidal process,) 
projecting downwards and backwards. This is marked by three vertical grooves ; the two lateral ones are rough, and receive 
the inferior borders of the pterygoid plates of the sphenoid bone ; the middle one, smooth, corresponds with and completes the 
fossa between the pterygoid plates. 

The vertical portion of the bone is flat and thin ; it presents two surfaces ; the internal one (nasal) is divided into two parts 
by a transverse ridge, which articulates with the inferior spongy bone ; the space below the ridge forms part of the inferior meatus, 
that above it of the middle meatus. The external surface, rough and unequal, is divided by a vertical groove, which is completed 
into a canal (posterior palatine canal) by the maxillary bone. The posterior part of this surface articulates with the rough bor- 
der and nasal surface of the maxillary bone ; and the anterior, thin and scaly, with the side of the antrum. 

The superior border of the vertical portion of the palate bone presents a notch, forming the greater part of a foramen, which 
is completed by the sphenoid bone when the parts are in their natural position. This is called the sphcno-palatine foramen ; and 
outside it is placed the nervous ganglion of the same name, (Meckel's ganglion.) This notch divides the border of the bone into 
two processes or heads, the sphenoidal and the orbital. 

The sphenoidal process, smaller and not so prominent, presents three surfaces, of which one, internal, looks to the nasal fossa ; 
another, external, forms a small part of the zygomatic fossa ; and the third, superior, grooved on its upper surface, articulates with 
the under surface of the sphenoid bone, and with it forms part of the pterygopalatine canal. 

The orbital process inclines outwards and forwards, and has five surfaces, two of which are free, and three articulated ; of 
the latter, the internal one rests against the ethmoid bone, and covers some of its cellules ; the anterior articulates with the superior 
maxillary bone ; and the posterior (which is hollow) with the sphenoid. Of the non-articular surfaces, one superior, smooth, and 
oblique, forms a small part of the floor of the orbit ; the other, external, looks into the zygomatic fossa. 

Articulations. — With the corresponding palate bone ; with the maxillary, ethmoid, sphenoid, vomer, and inferior spongy 
bone. 

Muscular attachments. — To its spine, the azygos uvulae ; to the centre groove on its tuberosity, a small part of the internal 
pterygoid ; and to the transverse ridge on the palate plate, the aponeurosis of the circumflexus palati. 

Developement. — From the position and complex relations of this bone, its mode of growth is difficult to be determined. It 
appears at first like a single osseous plate slightly curved, and produced from one centre of ossification. 

The Vomer. — The vomer, so called from its resemblance to a ploughshare, is flat, irregularly quadrilateral, and placed verti- 
cally between the nasal fossae, presenting two surfaces and four borders. The lateral surfaces form part of the inner wall of the 
nasal fossae ; the superior border, thick and deeply grooved, receives the rostrum of the sphenoid bone ; the margins of the groove 
expand and are articulated with two small lamellae at the roots of the pterygoid processes of the sphenoid bone. The anterior 
border, also grooved, presents two portions, into one of which is implanted the descending plate of the ethmoid, and into the other 
the nasal cartilage. The posterior border, dividing the posterior nares, is thin and unattached : the inferior is received into the 
fissure formed by the palate plates of the superior maxillary and palate bones. It is developed from a single osseous centre. 

The Inferior Turbinate Bone. — The inferior turbinate, or spongy bone, (so called from its texture in the latter case, in the 
former from some resemblance to the lateral half of an elongated bivalve shell,) extends from before backwards, along the side of 
the nasal fossa : — it appears as if appended to the side of the superior maxillary and palate bones. It is slightly convoluted, and 
presents an internal convex surface, projecting into the nasal fossa ; and an external concave one, which arches over the inferior 
meatus. Its superior border articulates with the ascending process of the maxillary bone before, with the palate bone behind, 
and in the centre with the os unguis ; it presents also a hooked process, which curves downwards and articulates with the side of 
the antrum ; the inferior border is free, slightly twisted, and dependent. It has one point of ossification. 

The Inferior Maxillary Bone. — The inferior maxilla (os maxillae inferior) is of considerable size, and forms a large portion 
of the sides and fore part of the face. It is convex in its general outline, and shaped somewhat like a horse-shoe. It is usually 
considered as divisible into a middle larger portion — its body, and two branches or rami. The body is placed horizontally ; its 
external surface is convex, and marked at the middle by a vertical line, indicating the original division of the bone into two lateral 
parts, and thence named its symphysis. On each side of the symphysis, and just below the incisor teeth, is a superficial depres- 
sion, (the incisor fossa,) which gives origin to the levator menti muscle; and, more externally, a foramen, (foramen mentale,) 
which transmits the terminal branches of the dental nerve and artery. A raised line may be observed to extend obliquely up- 
wards and outwards from near the symphysis to the anterior border of the ramus; it is named the external oblique line, and is 
intended to give attachment to muscles. The internal surface of the body of the bone is concave in its general outline, and 
marked at its centre by a depression corresponding with the symphysis ; at each side of which are two prominent tubercles placed 
in pairs, one above the other, and affording attachment,— the upper pair to the genio-hyo-glossi, and the lower to the genio-hyoidei 
Boxes. — 5 



34 

muscles; beneath these arc two slight depressions for the digastric muscles. An oblique prominent line (the mylo-hyoidean 
ridge) will be observed leading from the lower margin upwards and outwards to the ramus ; above the line is a smooth depres- 
sion for the sublingual gland, and beneath it, but situated more externally, is another for the submaxillary gland. The superior 
border of the body is horizontal, and marked by notches, corresponding with the alveoli, or sockets of the teeth. The inferior 
border, thicker at its anterior than at its posterior part, is slightly everted, so as to project somewhat forwards. 

The branches {rami) project upwards from the posterior extremity of the body of the bone, with which they form nearly a 
right angle in the adult, an obtuse one in infancy,— the "angle" of the jaw. They are thinner somewhat, and appear as if com- 
pressed. The external surface of each ramus is flat, and marked by slight inequalities ; the internal surface presents at its middle 
a foramen, {inferior denial,) leading into a canal (dental) contained within the bone, and lodging the dental nerve and vessels. 
Beneath the foramen, a slight groove marks the passage of some vessels and a nerve, the rest of the surface being rough, for the 
insertion of the pterygoideus interims. The anterior border of each ramus is nearly vertical in its direction, and terminates in a 
pointed extremity, named the coronoid process ; it is grooved at its commencement, for the attachment of the buccinator muscle. 
The posterior border is also almost vertical in adults ; but in children and edentulous subjects it departs considerably from this direc- 
tion, and approaches that of the base of the bone. This border is surmounted by a constricted part, which appears as if compressed 
from before backward, and is called the neck of the bone. It is slightly depressed at its fore part, and gives insertion to the ex- 
ternal pterygoid muscle. Now the neck supports the articular head of the bone, (the condyle,) which is convex and oblong, its 
greatest diameter being from without, inwards ; the direction of its axis is oblique, so that, if prolonged, it would meet with that 
of its fellow of the opposite side at the anterior margin of the foramen magnum. The interval between the condyle and the 
coronoid process, deeply excavated, is called the sigmoid notch, and if viewed when the bones are in silu, it will be found to 
form a complete circle with the arch of the zygoma. 

Attachments of muscles. — To the incisor fossa, the levator menti ; to the external oblique line, the depressor labii inferioris, 
depressor anguli oris, and a small part of the platysnia myoides. To the upper tubercles on the inner surface of the symphysis, 
the genio-hyo-glossi ; to the inferior ones, the genio-hyoidei ; to the depression beneath these, the digastricus ; to the internal 
oblique line, the mylo-hyoideus, and posteriorly a small part of the superior constrictor of the pharynx. To the external surface 
of the ramus, the masseter; to the lower part of the inner surface, the pterygoideus internus; to the neck of the condyle, the 
pterygoideus externus ; to the coronoid process, the temporal. 

PLATE XVIII. 

Anatomy of the humerus. 

Fig. 1, An anterior view of the humerus of the right arm : after Cheselden. 

No. 1 . The shaft of the humerus. 2. The rough surface upon its outer side, which gives attachment to the tendon of the deltoid muscle. 
3. The head of the bone. 4, 4. Its neck. 5. The greater tuberosity. 6. The lesser tuberosity. 7, 7. The bicipital groove. 8. 
The surgical neck of the bone. 9. The anterior bicipital ridge. 10. The posterior bicipital ridge. 11. The lower extremity of the 
bone. 12. The pulley-like surface which articulates with the ulna. 13. The rounded articular surface for the articulation of the 
head of the radius. 14. The external condyle. 15. The external condyloid ridge. 16. The internal condyle. 17. The internal 
condyloid ridge. 18. The fossa which receives the coronoid process of the ulna during flexion of the arm. 

Fig. 2. A posterior view of the humerus of the right arm : after Cheselden. 

No. 1. The shaft of the bone. 2. The prominence which corresponds with the insertion of the deltoid muscle. 3, 3. The musculo- 
spiral groove. 4. The head of the bone. 5,5. Its neck. 6. The greater tuberosity ; the number rests upon the surface for the 
attachment of the infra-spinatus muscle. 7. The surface for the attachment of the teres minor. 8. The surgical neck of the bone. 
9. The lower extremity of the humerus. 10. The pulley-like surface for the articulation of the ulna. 11. The external condyle. 
12. The external condyloid ridge. 13. The internal condyle. 14. The internal condyloid ridge. 15. The fossa for the reception 
of the olecranon process of the ulna. 

Fig. 3. Section of the humerus, showing its internal structure: after Cheselden. 

No. 1 The head of the bone 2, 2. The line of junction of the epiphysis of the head with the shaft of the bone. 3. The greater 
uberos.ty. 4, 4. The medullary canal of the bone. 5, 5. The solid walls of the bone. 6. The bottom of the fossa for the recep- 
Urble Cran0 "' fhe eXternal cond y le - 8 - ^ internal condyle. 9. The articular surface of the lower extremity of 

Fig. 4. The head of the humerus, seen upon the superior aspect of the bone 

N °" !hel h nd h on a o'f ft * r A ^ 1 ^ "f" f" l^ **** ^^ 5 the number rests "P°" that «*» which gives attachment to 
TeuZ L Les 'i 'or'" 13 " Tt , Th T rfaCe ^ tHe aUaChment ° f the -F-Pi-tus. 5. The surface for the attach- 
ment of the teres minor muscle 6. The lesser tuberosity of the humerus. 7. The bicipital groove. 

tie. 5. The lower extremity of the humerus. r ° 

Ftg. 6. An anterior view of the humerus of the right arm of a fcetus 

No. 1. Its shaft. 2. Its cartilaginous head and upper extremitv t tu m ■ 

cm upper extremity. S. The cartilaginous lower extremity. 



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Developement. — The growth is here effected from two osseous points, one in each lateral half. 

Os Hyoides. — This is the u-shaped bone, so named from some resemblance to the Greek letter v. It is occasionally called 
the lingual bone, from its important relations with the tongue; it is situated at the base of the tongue, and may be felt between 
the chin and the thyroid cartilage. It consists of a body, two cornua, and two cornicula. The body or central piece is small, 
quadrilateral in its form, and appearing as if compressed from before backwards ; hence the direction of its plane is nearly ver- 
tical ; but the great cornua seem as if compressed from above downwards, so that their plane appears horizontal. The anterior 
surface of the body is convex, and marked at the middle by a vertical line, on each side of which are depressions for the attach- 
ment of muscles ; its posterior surface is concave, and corresponds with the epiglottis. The cornua project backwards, and in a 
rounded point. The cornicula, short, irregularly conical in their form, and oblique in their direction, are placed at the junction of 
the body with the cornua, and give attachment to the stylo-hyoid ligament ; they continue for a long time movable, as the cartilage 
which connects them remains unossified to an advanced period of life. 

Attachments of muscles and ligaments. — The stylo-hyoid ligaments, to the cornicula; the thyro-hyoid, to the cornua. The 
anterior surface gives attachment to the stylo-hyoid, sterno-hyoid, and digastric muscles; the superior border, to the mylo-hyoid, 
genio-hyoid, genio-hyo-glossi, linguafis, hyo-glossus, and the middle constrictor of the pharynx; its lower border, to the omo-hyoid 
and thyro-hyoid muscles, and more internally to the thyro-hyoid membrane. 

The sutures. — The bones of the skull, and those of the face, are joined together by seams or sutures. The cranial sutures 
are commonly said to be five in number, of which three are termed true, as the margins of the bones are, in a manner, dove- 
tailed one into another ; and two are called false, or squamous, as they merely overlap one another, like the scales of fishes. The 
true sutures are, the coronal, the lambdoidal, and the sagittal. These names are obviously ill-chosen ; they convey no notion of 
the position which the sutures occupy in the skull or of the bones which they connect. 

The coronal suture (sutura coronalis) has been so named from being situated where the ancients wore their garlands, (coronae.) 
It connects the frontal with the two parietal bones, and hence it may with more propriety called "fronto-parietal." It commences 
at each side about an inch behind the external orbital process of the frontal bone, where the anterior inferior angle of the parietal 
articulates with the great wing of the sphenoid bone. From this point it mounts rather obliquely up towards the vertex, having 
an inclination backwards. The dentations are better marked at the sides than at the summit of the head, for in the latter 
situation the suture approaches somewhat the squamous character, to allow the frontal bone to overlap the parietal. A similar 
change takes place at its lower part or commencement, with this difference, that there the parietal bones are made to overlie 
the frontal. 

The lambdoid suture (sutura lambdoidalis) is situated between the occipital and the parietal bones, its form resembling some- 
what that of the Greek letter a, whence its name has been taken. It begins at each side on a line with the posterior inferior 

PLATE XIX. 

The bones of the fore-arm. 

Fig. 1. An anterior view of the bones of the right fore-arm : after Cheselden. 

No. 1. The shaft of the ulna. 2. The head of the bone. 3. The olecranon process. 1. The coronoid process. 5. The greater 
sigmoid notch. 6, 6. The rough border to which the broad extremity of the internal lateral ligament is attached. 7. The medul- 
lary foramen; upon the shaft of the bone. 8,8. The interosseous ridge of the ulna. 9. The lower extremity of the bone. 10. Its 
styloid process. 11. The shaft of the radius. 12. The medullary foramen. 13. The interosseous ridge. 14. The head of the 
bone. 15. Its neck. 1G. The tuberosity into which the tendon of the biceps muscle is inserted. 17. The lower extremity of the 
bone. 18. Its styloid process. 19. The surface which articulates with the scaphoid bone of the carpus. 20. The surface which 
articulates with the semilunar bone. 

Fig. 2. An ulna of the left arm, viewed upon its external or radial side : after Cheselden. 

No. 1. The shaft of the ulna. 2. The olecranon process of the head of the bone. 3, 3. The greater sigmoid notch, for articulation with 
the trochlea of the humerus. 4. The lesser sigmoid notch, for articulation with the head of the radius. 5. The coronoid process. 
C. The surface for the attachment of the anconeus muscle. 7, 7. The interosseous ridge. 8. The inferior extremity of the ulna. 
9. Its styloid process. 

Fig. 3. A front view of the head of the left ulna. 

No. 1. The upper part of the olecranon. 2. The coronoid process. 3, 3. The greater sigmoid notch, for articulation with the humerus. 
4. The lesser sigmoid notch, for articulation with the head of the radius. 5. The upper part of the shaft of the bone. 

Fig. 4. The head of the ulna, viewed upon its antero-external aspect. 

The references are the same as for the preceding figure, with the addition of 6. The surface for the attachment of the anconeus. 

Fig. 5. The lower extremity of the ulna, viewed from below. 

No. 1. The surface which articulates with the inter-articular fibro-cartilage. 2, 2. The surface which articulates with the lower ex- 
tremity of the radius. 3. The styloid process of the ulna. 

Fig. (5. The head of the radius, viewed from above; and showing the cup-like form of the head of the bone. 

Fig. 7. The lower extremity of the radius. 

No. 1. Its styloid process. 

Fig. 8. The radius and ulna of a foetus, showing the cartilaginous epiphyses of the bones. 



36 

angle of the parietal bone, and thence inclines upwards and forwards to the point at which the two parietal bones are joined by 
the sagittal suture. It thus represents two sides of a triangle. It is often interrupted by accessory osseous deposits, (ossa 
Wormiana.) From its position and relation this suture may be named « occipitoparietal." 

The mgittal suture (s. sagittalis-sagitta, an arrow) extends directly backwards, from the middle of the coronal to that of 
the lambdoid suture, and connects the two parietal bones, from which circumstance it may be called the « inter-parietal" suture: 
in children, and occasionally in adults, it is prolonged through the frontal bone, even to the root of the nose. The serrated 
appearance of the sutures is perceptible only on the external surface of the bones; the internal surface, or table of each, as it is 
called, being merely in apposition with the contiguous bone. 

The line of union between the occipital and the temporal bone at each side used to be considered as a continuation of the 
lambdoid suture, or as an appendix to it, and was accordingly named additamentum suturse lambdoidalis. It may, however, 
be named tempora-occipital, as it connects the mastoid and petrous parts of the temporal bone with the occipital-principally its 
basilar and condyloid portions. In this suture there are no regular dentations ; in a great part of its extent the margins of the 
bones are merely in apposition. 

The squamous sutures (sutura? squamosa;) are arched, and mark the junction of the lower borders of the parietal bones with 
the squamous parts of the temporal, their edges being so bevelled off as to allow the latter to overlie the former. At the point 
of junction between the squamous and mastoid parts of the temporal bone, the true squamous suture ceases ; but from 
thence a short suture runs backwards to the lambdoid, connecting the mastoid part of the temporal with the postero-inferior angle 
of the parietal. This is termed additamentum suturese squamosa .-—both together form the " temporo-parietal" suture. 

The line of direction of the sutures (particularly the lambdoid and sagittal) is not unfrequently interrupted by additional 
bones, inserted between those hitherto enumerated. These, from being sometimes of a triangular form, are called ossa triquetra, 
and also ossa Wormiana. 

The cranial bones are joined to those of the face by sutures, which are common to both sets of bones. The transverse 
suture, observable at the root of the nose, extends across the orbits, and connects the frontal with the nasal, superior maxillary, 

PLATE XX. 

The bones of the wrist and hand. 

Fio. 1. A front view of the right wrist and hand: after Cheselden. 

No. 1. The scaphoid bone. 2. The semilunar bone. 3. The cuneiform bone. 4. The pisiform bone. 5. The os trapezium. 6. The 
os trapezoides. 7. The os magnum. 8. The unciform bone. 9. Its hook-like process. 10. The metacarpal bone of the thumb. 
11. The metacarpal bone of the index finger. 12. Its broad base, articulating with three bones of the carpus; the rough surface 
immediately below the figure is foi the insertion of the tendon of the flexor carpi radialis. 13. The metacarpal bone of the middle 
finger. 11. The metacarpal bone of the ring finger with its small base. 15. The metacarpal bone of the little finger. 16. The 
first phalanx of the thumb. 17, 17. The first phalanges of the four fingers. 18, 18. The second phalanges of the fingers. 19,19. The 
last phalanges of the fingers. 20. The last phalanx of the thumb. 

Fig. 2. A posterior view of the right wrist and hand : after Cheselden. 

No. 1. The scaphoid bone. 2. The semilunar bone. 3. The cuneiform bone. 4. The os trapezium. 5. The os trapezoides. 6. The 
os magnum. 7. Its rounded head. 8. The unciform bone. 9. The metacarpal bone of the thumb, articulating with the os 
trapezium. 10. The metacarpal bone of the index finger, articulating with the os trapezium, os trapezoides, and os magnum. 
11. The depression for the insertion of the tendon of the extensor carpi radialis longior. 12. The metacarpal bone of the middle 
fincrcr, articulating with the os magnum only. 13. The depression for the insertion of the tendon of the extensor carpi radialis 
brevior. 14. The metacarpal bone of the ring finger. 15. The metacarpal bone of the little finger, articulating with the os unciforme. 
16. The depression of insertion for the tendon of the extensor carpi ulnaris. The other numbers of reference are the same as in the 
preceding figure. 

Fig. 3. The bones of the carpus; showing the surfaces of the second row, which articulate with the metacarpal bones: after 
Cheselden. 

No. 1. The surface of the os trapezium, which articulates with the metacarpal bone of the thumb. 2. The process on the palmar surface 
of the os trapezium, which overhangs the groove for the tendon of the flexor carpi radialis. 3. The os trapezoides. 4. The os 
magnum. 5. Its rounded head. 6. The unciform bone. 7. Its hook-like process. 8. The scaphoid bone. 9. The semilunar 
hone. 10. The cuneiform bone. 11. The pisiform bone. 

Fig. I. Separate bones of the carpus. 

No. 1. The scaphoid bone. 2. Its concave surface. 3. Its broad extremity. 4. Its pointed extremity or tuberosity. 5. The semilunar 
bone. 6. The concave articular surface of the bone. 7. Its convex articular surface. 8. Its palmar extremity. 9. The cuneiform 
bone. 10. Its broad extremity. 11. Its apex. 12. The pisiform bone. 13. Its articular facet. 14. The os trapezium, viewed 
upon ns dorsal aspect. 15. The surface which articulates with the metacarpal bone of the thumb. 16, The os trapezoides. 17. The 
os magnum. 18. Its rounded head. 19. Its dorsal surface. 20. The surface which articulates with the middle metacarpal bone. 
21. The unciform bone. 22. Its hook-like process. 

Fig. 5. The hand and wrist of the fcetus; after Cheselden. 

The carpus is wholly cartilaginous, as are the extremities of the metacarpal bones and phalanges, 
-arnoid bone, newed upon Us convex and upon its articular surface. 



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37 

ossa unguis, ethmoid, sphenoid, and malar bones. The zygomatic sutures are very short ; they are directed obliquely down- 
wards and backwards, and join the zygomatic processes of the temporal with the malar bones. The ethmoid suture surrounds 
the bone of the same name ; so does the sphenoid ; they are necessarily complex in consequence of the many relations of these 
bones. The lines of connexion between the nasal and maxillary bones, though sufficiently marked, have not received particular 
names ; but those observable between the horizontal lamellse of the latter, and those of the palate bones, may be termed the 
palato-maxillary sutures. 

Remarks on the general conformation of the Skull. — After having described, in detail, the separate bones of the head and 
face, it becomes necessary to review them collectively. The description of these bones forms the most difficult part of human, 
as well as of comparative osteology, as they are the most complex in the whole skeleton ; but a correct knowledge of them is 
indispensable, in consequence of the many important parts which they serve to sustain and enclose ; viz. the cerebral mass, with 
its nerves and vessels ; the organs of sight, hearing, smell, and taste ; part of those of mastication and deglutition, as well as of 
voice. To facilitate the description of the numerous eminences, depressions, cavities, and foramina of the skull, anatomists 
examine successively its external and internal surface : the former may be considered as divisible into five regions, three being 
somewhat of an oval figure, and situated, one superiorly, another at the base, the third in front, including the face ; the others 
comprise the lateral parts, and are somewhat flat and triangular. 

The superior region extends from the frontal eminences to the occipital protuberance, and, transversely, from one temporal 
ridge to the other ; it thus includes the upper broad part of the frontal, almost all the parietal, and the superior third of the occipital 
bone, which together form the vaulted arch of the skull. It is divided into two symmetrical parts by the sagittal suture and its 
continuation when it exists ; it presents no aperture or other inequality deserving of particular notice ; it is covered by the 
common integument and occipito-frontalis muscle, on which ramify branches of the temporal, occipital, and auricular arteries, as 
well as filaments of nerves from the frontal branches of the fifth and portio dura, and also from the occipital nerve. 

The inferior region, also oval in its outline, is the most complex of all, as it includes the entire base of the skull, extending 
from the incisor teeth to the occipital protuberance, and, transversely, from the mastoid process and dental arch on one side, to 
the corresponding points on the other. It may be considered as divisible into three parts. Of these, one corresponds with the 
extent of the arch of the palate ; it is divided into two parts, by a line extending from before backwards, and marking the junction 
of the palate processes of the superior maxillary and palate bones; this is intersected by another, running transversely between 
each palate bone and the corresponding maxillary bone. Anteriorly, and in the middle line, is a foramen, (the anterior palatine,) 
which in the floor of the nares is double, but becomes single inferiorly, and transmits the naso-palatine nerve ; posteriorly, on each 
side, and at the base of the alveolar border, is another foramen, (posterior palatine,) for the posterior palatine nerves and artery. 
The middle, or guttural region, is bounded at each side by a line extended from the pterygoid process as far as the mastoid 
process, thus including the posterior aperture of the nares, and the central part of the base of the skull. In the centre is situated 
the basilar process of the occipital bone, marked by slight inequalities for the attachment of muscles, and towards its posterior 
extremity the anterior condyloid foramina, which transmit the ninth pair of nerves. On each side is the pars petrosa of the tem- 
poral bone, in which may be observed the styloid and vaginal processes; more posteriorly is the jugular fossa, which is completed 
into a foramen (foramen lacerum posterius basis cranii) by the border of the occipital bone. This is divided into two parts by 
a spicula of bone, or a fibrous band, the internal and anterior one serving to transmit the glossopharyngeal, par vagum, and spinal 
accessory nerves; the other the jugular vein. Between the apex of the pars petrosa, and the side of the basilar process, and the 
body of the sphenoid bone, is the foramen lacerum anterius basis cranii, which is closed inferiorly by a thin plate of cartilage : 
across its area, as viewed at its upper or cerebral aspect, runs the internal carotid artery in its passage from the carotid canal in 
the temporal bone to the side of the sphenoid, and also the Vidian nerve, after it has passed backwards through the pterygoid 
foramen, and is proceeding to reach the groove in the upper surface of the pars petrosa. Between the contiguous margins of the 
pars petrosa and the great ala of the sphenoid bone is a groove, which leads backwards and outwards, and lodges the cartilaginous 
part of the Eustachian tube ; and above the osseous part of that tube, and separated from it by a thin lamella of bone, is the orifice 
of the canal which transmits the tensor tympani muscle. The foramina of this region, taken in their order, from within outwards 
and backwards, are, the foramen ovale, foramen spinosum, foramen caroticura, and stylo-mastoideum. 

The anterior part of this region is continuous with the posterior aperture of the nares, which is divided into two parts by the 
vomer. It is bounded above by the body of the sphenoid bone, below by the palate plates of the ossa palati, and on the sides by 
the pterygoid processes. The pterygoid groove, in each of these processes, is completed inferiorly by the pyramidal process of the 
palate bone ; near its junction with the body of the bone is the scaphoid fossa, for the origin of the circumflexus palati ; and at its 
inferior termination is the hamular process, round which the tendon of that muscle is reflected. Between the base of this process 
and the posterior palatine foramen is situated a smaller foramen, leading down from the posterior palatine canal, and which 
transmits the middle palatine nerve. 

The posterior part of the inferior region includes all that is situated between the occipital protuberance and a line connecting 
the mastoid processes. It is divided into two lateral parts by a ridge, extending to the foramen magnum from the occipital protu- 
berance, from which two rough curved lines branch outwards, giving attachment to muscle the space 1>< tween the lines, 



and that between the inferior one and the foramen magnum. At the margin of the foramen, but nearer to its anterior termination, 
arc the condyles of the occipital bone which articulate with the first vertebra; behind each is a depression, {condyloid fossa,) and 
usually a foramen, (posterior condyloid foramen,) which transmits a small vein and artery. Before and a little to the outer side 
I., in a spot also retiring and depressed, is the opening of the anterior condyloid foramen, which looks obliquely outwards 
and forwards, and transmits the lingual nerve. 

PLATE XXL 

The ligaments of the elbow-joint, fore-arm, and wrist-joint. 

Fig. 1. The ligaments of the elbow-joint and fore-arm, seen from the front. 

No. 1. The lower part of the humerus. 2. The internal condyle. 3. The external condyle. 4. The projection formed by the head of 
the radius. 5. The coronoid process of the ulna. 6. The border of the greater sigmoid notch. 7, 7. The anterior ligament of the 
elbow-joint. 8. The internal lateral ligament. 9. The orbicular ligament of the head of the radius. 10. Some few of the anterior 
fibres of the external lateral ligament passing down to be inserted into the orbicular ligament. 11. The radius. 12. The ulna. 
13. The oblique ligament. 14, 14. The interosseous ligament. 15. The opening which transmits the anterior interosseous artery. 
16. The anterior ligament of the inferior radio-ulnar articulation. 17. The triangular fibro-cartilage of the inferior radio-ulnar 
articulation. 

Fio. 2. The ligaments of the elbow-joint and fore-arm, seen from behind. 

No. 1. The lower extremity of the humerus. 2. The internal condyle. 3. The external condyle. 4. The olecranon process of the 
ulna. 5. A projection made by the head of the radius. 6. The posterior ligament thrown into folds by the extension of the joint. 
7. A part of the posterior ligament. 8. The external lateral ligament of the elbow. 9. Its posterior fibres, which are inserted into 
the ulna. 10. The orbicular ligament of the superior radio-ulnar articulation. 11. The radius. 12. The ulna. 13, 13. The inter- 
osseous ligament. 14. The opening in the interosseous ligament for the passage of the anterior interosseous artery. 15. The 
posterior ligament of the inferior radio-ulnar articulation. 

Fig. 3. Ligaments of the elbow-joint, viewed from the inner side. 

No. 1. The lower extremity of the humerus. 2. Its internal condyle. 3. The olecranon. 4. The ulna. 5. The radius. 6. The 
internal lateral ligament of the elbow. 7. Its anterior fibres continued downwards on the coronoid process of the ulna. 8. Its 
posterior fibres going to be attached to the side of the olecranon. 9. The anterior ligament of the articulation. 10. The orbicular 
ligament surrounding the head of the radius. 11. The tendon of the biceps curving around the radius to its insertion. 12. The 
upper part of the interosseous ligament. 

Fig. 4. Ligaments of the elbow-joint, viewed from the outer side. 

No. 1. The lower extremity of the humerus. 2. The outer condyle. 3. The olecranon process of the ulna. 4. The ulna. 5. The 
radius. G. Its tuberosity, seen from behind. 7. The neck of the radius. 8. The external lateral ligament. 9. Its posterior fibres 
passing backwards to be inserted into the border of the olecranon. 10. The orbicular ligament. 11. The anterior ligament of the 
joint. 12. The posterior ligament. 13. The interosseous ligament. 

Fig. 5. The elbow-joint, flexed, and seen from behind. 

No. 1. The lower extremity of the humerus. 2. The internal condyle. 3. The external condyle. 4. The upper part of the olecranon. 
5. The poster.or ligament of the articulation. 6. The posterior part of the internal lateral ligament. 7. The external lateral ligament. 

Fig. 6. The elbow-joint laid open from the front, in order to show the reflections of the synovial membrane 

No. I. The lower extremity of the humerus. 2. Its internal condyle. 3. Its external condyle. 4. Its articular surface covered with 
cartilage. 5. The ulna 6 The radius. 7. The external lateral ligament. 8. The internal lateral ligament. 9, 9. The anterior 
if men" TZ \ J" ' \ ^^ ^^^ *** int ™ S betWeen lhe head of *" ^ius and the orbicular 

£ r • A: x "Sr 1 membrane which is reflected between the head ° f the radius - *• »— %— -* ° f 

Fig. 7. The ligaments of the wrist-joint, viewed from the radial aspect 

N °' p'JcTs oTthe radial '"I ^ ? ^T^r ** ^^ °' *' ^"^ mUSCleS ° f the thumb and of *' wrist 3. The styloid 
ilamen The d rsalt^T "T^ ^ *" WriSH ° int - 5 ' The ^ lior "««»«' of the *ri* *■ The anferior 

oCtt thVjldl^rr ° nneC K tmgthe C3rPal b ° neS - 8 - The Sma11 e " d of ^e scaphoid bone. 9. The ligament 
connecting me scaphoid with the trapezium bone. 10 ThP pyioit.^1 k„,j c .i • b 

the carpal bone, 12. The pisiform bone. 13. Th unc J m bone 14 T ^^ ft."" The P aIm - ^-nts of 

bands connecting the metacarpal bones with each o h »16 The tendl f Z ^^^f. ] ^™^ ^ The 

insertion. 17. The tendon of the extensor carpi rad a is b rev' J *' ^™ «*°™*™ ™W ^»l«f* ™ off Cose to it, 

19. The tendon of the extensor ossis metacarpi pollicis divided! J!' . P ' Car P°- metacar P al h S ament of the thumb " 

31. Part of the metacarpal bone of the fore-finger. ' nSertl0n - ^ Part ° f the metacar P*l bone of the thumb. 

Fig. 8. The ligaments of the wrist-joint, viewed from the ulnar aspect 

No. 1. The lower part of the ulna. 2. Its styloid process ? Th„ ;' . ,, 

5. The cuneiform bone. 6. The hook-like process of the 1 f u ^^ ° f the wrist "Joint. 4. The pisiform bone, 

ligament. 9, 9. The dorsal ligaments of the carpal bones 0^,1 ? " T** anteri ° r Hgament ° f lhe Wrist ' 8 ' The P° Sleri ° r 
carpometacarpal ligaments 1* 12 Transverse I d lu< lne P almar 1'gaments of the carpal bones. 11, 11. The dorsal 

extensor carpi ulnar!,, divided close to its insertion ""J u™^"? *" ^^ ° f ^ metacar P al bones - 13. The tendon of the 
bones and the latter with the fifth metacarpal bone ' K P r lntcrnal lateral ligaments connecting the two ranges of the carpal 
bone of the thumb. 17. The capsular nrnn mB , ' 1 r ® metacar r a l bone of the little finger. 16. Part of the metacarpal 

capsular carpo-metacarpal ltgament of the thumb. 



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The anterior region of the skull is of an oval form, and extends from the frontal eminences to the chin, and from the external 
border of the orbit and ramus of the jaw, on one side, to the corresponding points on the other, so as to include the whole of the 
face. The eminences, depressions, fossae, and foramina, observable in this region, are as follow, viz. the frontal eminences more 
or less prominent in different individuals, bounded inferiorly by two slight depressions, which separate them from the superciliary 
ridges ; these curve outwards, from the nasal process of the frontal bone. Beneath the superciliary ridge, on each side, is the 
margin of the orbit, marked at its inner third by a groove, or a foramen, which transmits the frontal nerve and supra-orbital 
artery ; and also by a slight depression, which gives attachment to the cartilaginous pulley of the trochlearis muscle. At an 
interval corresponding with the breadth of the orbit is another ridge, forming its inferior margin ; under which is situated the 
infra-orbital foramen, for the passage of the superior maxillary nerve ; and still lower down, the fossa canina, which gives attach- 
ment to the levator anguli oris muscle ; it is bounded below by the alveolar border of the upper jaw, and surmounted by the 
malar tuberosity. Towards the middle line, and corresponding with the interval between the orbits, is the nasal eminence of the 
frontal bone, which is prominent in proportion to the developement of the frontal sinuses over which it is situated. This is 
bounded by the transverse suture, marking the root of the nose. Beneath the nasal, and between the contiguous borders of the 
superior maxillary bones, is a triangular opening which leads into the nasal fossae ; it is broad below, and there its edge is sur- 
mounted by a prominent process, the nasal spine. Latterly it presents two sharp curved borders, which gradually incline inwards 
as they ascend to the nasal bones, so as to narrow it somewhat. Below the nasal aperture is a slight depression (myrtiform fossa) 
at each side of the middle line over the alveolus of the second incisor tooth. Farther down is the transverse rima of the mouth, 
between the alveolar borders of the jaws. In the inferior maxillary bone, besides some muscular impressions, is the mental 
foramen, which transmits the terminal branches of the dental nerve and artery. 

The two lateral regions of the skull are somewhat of a triangular figure, the apex of the triangle being at the angle of the 
lower jaw, the base at the temporal ridge, and the sides formed by two lines drawn, one upwards and forwards, over the external 
orbital process, the other upwards and backwards over the mastoid process. In consequence of the great irregularity of the surface, 
it is necessary to subdivide each of these regions into three ; the part above the zygoma being called the temporal region or fossa, 
that beneath it the zygomatic, the remainder being named the mastoid. 

The temporal region, or fossa, being bounded by the temporal ridge above, and by the zygomatic arch below, is of 9 semi- 
circular form, and extends from the external angular process of the frontal bone to the base of the mastoid process. It is filled 
up by the temporal muscle, lodges the deep temporal vessels and nerves, and is formed by the temporal, parietal, frontal, sphenoid, 
and malar bones. 

The mastoid region is bounded before by the transverse root of the zygoma, above by the horizontal one and the addita- 
mentum suturae squamosa?, behind and inferiorly by the additamentum suturse lambdoidalis. Proceeding from behind forwards, 
we observe the mastoid foramen, the process of the same name, anterior to which is the aperture of the meatus auditorius externus, 
which is circular in young subjects and somewhat oval in adults, the greatest diameter being from above downwards. The osseous 
tube continuous, externally, with the fibro-cartilage of the ear, and bounded, internally, by the membrana tympani, is directed, 
obliquely, forwards and inwards, and is somewhat broader at its extremities than in the middle. Anterior to the meatus 
is the glenoid fossa, which is bounded before by the transverse root of the zygoma, behind by the meatus, and internally by 
the spinous process of the sphenoid bone. It is divided into two parts by a transverse fissure, (fissura Glasseri,) the 
anterior portion being smooth, for its articulation with the condyle of the lower jaw ; the posterior, rough, lodges part of the parotid 
gland. This fissure gives entrance to the laxator tympani muscle and a small artery, and transmits outwards the chorda tympani 
nerve. 

The zygomatic region, situated deeply behind and beneath the orbit, is bounded before by the convex part of the superior 
maxillary bone, and is enclosed between the zygoma and the pterygoid process. The posterior surface of the maxillary bone is 
pierced by some small foramina, opening into canals, for the transmission of the superior dental nerves. Between the superior 
border of this bone, and the great ala of the sphenoid, is a fissure, {spheno-maxillary,) which is directed forwards and outwards, 
and communicates with the orbit; and between its posterior border and the pterygoid process is another, {ptery go-maxillary,) 
whose direction is vertical. The angle formed by the union of these fissures constitutes the spheno-maxillary fossa, which is 
situated before the base of the pterygoid process, behind the summit, or posterior termination, of the orbit, and immediately external 
to the nasal fossae, from which it is separated by the perpendicular plate of the palate bone. Into this narrow spot five foramina 
open, viz. the foramen rotundum, which gives passage to the second branch of the fifth pair; the foramen pterygoideuni, to the 
Vidian or pterygoid nerve and artery ; the pterygopalatine, to a small artery of the same name, (sometimes called also the superior 
pharyngeal ;) the posterior palatine foramen, leading to the canal of the same name ; and the spheno-palatine, which transmits 
the spheno-palatine nerve and artery. 

The internal surface of the skull may be divided into its arch and its base. The arch extends from the base of the perpen- 
dicular part of the frontal bone, as far as the transverse ridge on the inner surface of the occipital bone. Along the middle line. 
and corresponding with the direction of the sagittal suture, is a shallow groove, marking the course of the superior longitudinal 
sinus. Several slight irregular depressions may also be observed, for the cerebral convolutions, and some tortuous lines for the 



10 
t • „ MC irr^o-nlir rlenressions over the points occupied by glandulae Pacchioni. The 

,he amcri"; tme o/m7brain , it is marked by eminences and depressions corresponding „«h .he ccrebra! convohu.ons and sole, ; 

th. ta^£fc middle lobe of .he brain. It is marked by linear impressions for ,he memngeal artery and by shallow 
„" sKe ccrebm convolnnons; an.erior.y i. opens in.o .he orbi. by .he sphenoidal assure, somehmes ca led foramen lacerum 
amerl .odisungnishi. from .hose placed farther back, and already no.iced , it .ransmus .he .h.rd, .he fourth, and the »»h 

PLATE XXII. 

The ligaments of the wrist and hand. 

Fig. 1. The ligaments of the anterior aspect of the wrist and fingers. _ 

No 1 The lower part of the radius. 2. The lower part of the ulna. 3. The inferior part of the interosseous ligament. 4. The 
anterior ligament of the inferior radio-ulnar articulation. 5. The anterior ligament of the wrist-joint. 6. The external lateral liga- 
ment. 7.°The internal lateral ligament. 8. The pointed extremity of the scaphoid bone. 9. The ridge of the trapezium. 
10 The pisiform bone. 1 1. The hook-like process of the unciform bone. 12. The anterior prominence of the os magnum. 13, 13. 
Anterior ligaments of the carpal bones. 14, 14. Lateral ligaments of the carpus. 15, 15. Anterior ligament of the carpometa- 
carpal articulation. 16. The capsular ligament of the carpo-metacarpal articulation of the thumb. 17. A strong ligament passing 
between the pisiform bone and the hook -like process of the unciform bone. 18. The tendon of the extensor ossis metacarpi pollicis, 
divided close to its insertion. 19. One of the lateral ligaments of the metacarpophalangeal joint of the thumb- 20, 20. Sesa- 
moid bones of this articulation. 21. One of the lateral ligaments of the phalangeal articulation of the thumb. 22. Anterior 
ligament of the metacarpophalangeal articulation of the index finger. 23, 23. Lateral ligaments of the metacarpo-phalangeal arti- 
culation of the index finger. 24, 24. Transverse ligaments. 25, 25. Anterior ligaments of the phalangeal articulations of the index 
finger. 2G, 26. Lateral ligaments of the phalangeal articulations of the index finger. 27, 27. The theca of the flexor tendons laid 
open through its entire extent in the middle finger. 28. The theca of the flexor tendons unopened : farther onwards, the theca is 
laid open, and the tendons are exhibited. 29, 29. The tendon of the deep flexor, bifurcating into two slips, between which the 
tendon of the superficial flexor passes on to the last phalanx. 30. The tendon of the superficial flexor. 31. The tendon of the 
deep flexor muscle, dividing into two slips. 

Fig. 2. The ligaments of the posterior aspect of the wrist and fingers. 

No. 1. The lower part of the radius. 2. Its styloid process. 3. The lower part of the ulna. 4. Part of the interosseous ligament. 
5. The posterior ligament of the inferior radio-ulnar articulation. 6. The posterior ligament of the wrist-joint. 7. The internal lateral 
ligament. 8. The external lateral ligament. 9, 9. The posterior ligaments of the carpus. 10, 10. The dorsal carpo-metacarpal 
ligaments. 11, 11. Transverse bands connecting the bases of the metacarpal bones of the fingers. 12. The capsular ligament of 
the carpo-metacarpal articulation of the thumb. 13. The tendon of the extensor ossis metacarpi pollicis, divided closje to its 
insertion. 14. One lateral ligament of the metacarpo-phalangeal articulation of the thumb. 15. One of the sesamoid bones 
of the metacarpo-phalangeal articulation of the thumb. 16. One of the lateral ligaments of the phalangeal articulation of the 
thumb. 17. The tendon of the extensor secundi internodii pollicis muscle, divided close to its insertion. 18, 18. The lateral liga- 
ments of the metacarpo-phalangeal articulation of the index and middle fingers. 19. The cavity of the articulation of the index 
finger. 20. The synovial membrane drawn aside in order to show the cavity of the articulation in the middle finger. 21, 21. The 
lateral ligaments of the phalangeal articulations of the index and middle fingers. 22, 22. The cavity of the articulation exposed 
in the middle finger by drawing aside the synovial membrane. 23, 23. The transverse ligament connecting the heads of the meta- 
carpal bones. 24, 24. The tendon of the extensor communis digitorum muscle covering the dorsal surface of the ring and little 
fingers, and concealing the articulations. 

Fig. 3. Vertical section of the carpus, showing the interosseous ligaments connecting the different bones, with the synovial cavity 
between them. 

No. 1. The scaphoid bone. 2. The os semilunare. 3. The os cuneiforme. 4. The os trapezium. 5. The os trapezoides. 6. The os 
magnum. 7. The os unciforme. 8. The base of the metacarpal bone of the index finger. 9, 9. The bases of the metacarpal 
bones of the three other fingers. 10, 10. The synovial cavity between the first and second range of carpal bones. 11, 11. The 
synovial cavity between the second range and the metacarpal bones. 12, 12. The carpal portion of the synovial membrane of the 
wrist-joint. 13. The interosseous ligament connecting the scaphoid with the semilunar bone. 14. The interosseous ligament con- 
necting the os semilunare with the os cuneiforme. 15. The ligament connecting the os magnum with the scaphoid bone and os 
trapezoides. 16. The ligament connecting the os magnum with the os unciforme. 17, 17. The interosseous ligaments connecting 
the bases of the metacarpal bones. 

Fig. 4. The inferior articular surface of the bones of the fore-arm, showing the triangular fibro-cartilage. 

No. 1. The articular surface of the radius. 2. The triangular fibro-cartilage. 3. The styloid process of the ulna. 

Fig. 5. Vertical section of a finger, showing the lateral ligaments and the cavities of its articulations. 

Nos. 1,1. Lateral ligaments. 2, 2. Cavities of the articulations. 



Boned 



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41 

nerves, together with the ophthalmic branch of the fifth and the ophthalmic vein. Behind this is situated the foramen rotund nm 
for the second branch of the fifth, the foramen ovale for the third, and, lastly, the foramen spinosum for the middle meningeal 
artery. Where the summit of the pars petrosa approaches the body of the sphenoid bone, there the internal orifice of the carotid 
canal opens. On the anterior surface of the pars petrosa, and directed obliquely backwards, there is a slight groove, leading to 
the hiatus Fallopii, and transmitting the Vidian nerve. 

The posterior fossa, deeper and broader than the others, gives lodgment to the lateral lobes of the cerebellum. In the pos- 
terior surface of the pars petrosa, which forms the boundary of this fossa, may be observed the internal auditory foramen, and, 
within a few lines of it, a triangular fissure, which opens into the aquasductus vestibuli, and towards its inferior margin part of the 
groove for the lateral sinus, which leads down to the foramen lacerum posterius. Along the middle line, and taking the parts 
situated in the base of the skull from before backwards, we observe the crista galli of the ethmoid bone, and on each side the 
cribriform lamella of that bone ; farther back, a slightly depressed surface, which supports the commissure of the optic nerves ; 
and on each side the optic foramina. Behind this is the pituitary fossa, situated on the body of the sphenoid bone, bounded 
before and behind by the clinoid processes. Leading downwards and backwards from these is the basilar groove, which supports 
the pons Varolii and medulla oblongata, and terminates at the foramen magnum : at each side of this foramen are the condyloid 
foramina, and behind it a crista, leading upwards to the occipital ridge, and giving attachment to the falx cerebelli. 

The Orbits. — The form of the orbits is that of a quadrilateral pyramid, whose base is directed forwards and outwards, and 
apex backwards and inwards, so that if their axes were prolonged backwards they would decussate on the body of the sphe- 
noid bone. 

The roof of each orbit forms part of the floor for the brain ; it is concave, and composed of the orbital process of the frontal, 
and the smaller wing of the sphenoid bone : at its anterior and inner border may be observed a depression for the attachment of 
the pulley of the trochlearis muscle ; externally, and immediately within the margin of the orbit, a shallow depression for the 
lachrymal gland ; at the anterior border, a groove, sometimes a foramen, which transmits the supra-orbital or frontal nerve and 
artery ; and posteriorly, at the apex of the cavity, the optic foramen, transmitting the optic nerve and ophthalmic artery. The 
floor forms the roof of the maxillary sinus : it consists of the orbital processes of the malar and maxillary bones, and of the 
small portion of the palate bone which rests on the latter ; towards the inner and anterior border, near the lachrymal canal, may 
be observed a slight roughness, for the attachment of the obliquus inferior muscle ; posteriorly, a groove, terminating in the infra- 
orbital canal, which runs nearly horizontally forwards. The inner side or wall of the orbit runs directly backwards, being 
parallel with the corresponding side of the other orbit, and is composed of the ascending process of the maxillary bone, the os 
unguis, the os planum of the ethmoid, and part of the body of the sphenoid bone. Near the anterior border is situated the lachrymal 
canal, which is formed, for the most part, between the ascending process and body of the maxillary bone, the remainder being made 
up by the groove in the os unguis, and a small process of the inferior spongy bone; this canal, a little expanded at its extremities, is 
directed downwards, backwards, and a little outwards. The outer side of the orbit, composed of the orbital plates of the malar 
and sphenoid bones, presents some minute foramina, which transmit small nerves from the orbit to the temporal fossa. 

The superior internal angle, formed by the junction of the orbital process of the frontal bone with the os unguis and os 
planum, presents two foramina, {foramen orbitale internum, anterius, et posterius,) which give transmission, the anterior to the 
nasal twig of the ophthalmic nerve, the posterior to the ethmoidal artery. The internal inferior angle is rounded off so as to be 
scarcely recognised ; it is formed by the union of the os unguis and os planum with the orbital plates of the superior maxillary 
and palate bones. In the external superior angle, formed by the malar, frontal, and sphenoid bones, is observed the sphenoidal 
fissure, of a triangular form, situated obliquely, its base being internal and inferior, the apex external and superior. In the 
inferior external angle, formed by the malar, the great ala of the sphenoid, the maxillary and palate bones, is situated the spheno- 
maxillary fissure, inclined at an angle with the former, and communicating Avith it, but of a different form, being broad at its 
extremities, and narrow at the centre. 

The anterior extremity, or base, of the orbit, is directed outwards and forwards ; and, as if to provide for a free range of 
lateral vision, the external wall retreats in some degree, and does not extend as far forward as the internal. The inner termina- 
tion of the cavity, representing the summit of a pyramid, to which it has been likened, corresponds with the optic foramen. In 
each orbit, parts of seven bones are observed, viz. the frontal, ethmoid, sphenoid, os unguis, malar, maxillary, and palate bones ; 
but as three of these, viz. the ethmoid, sphenoid, and frontal, are common to both, there are only eleven bones for the two orbits. 

The Nasal Fossse. — These fossae are two cavities, placed one at each side of the median line, separated by a flat vertical 
septum. They communicate, by foramina, with the various sinuses lodged in the frontal, the ethmoid, and superior maxillary 
bones, and open anteriorly, on the surface, by the nares, and posteriorly into the pharynx. The roof, the floor, the inner and the 
outer walls of these cavities, require a separate consideration. 

The roof is flat at its middle part, and sloped before and behind ; it is formed in front by the inner surface of the nasal 1 

behind by the body of the sphenoid, and in the middle by the horizontal or cribriform lamella of the ethmoid bone. The floor. 

smooth, concave from side to side, and formed by the palate plates of the maxillary and palate bones, extends backwards, and a 

little downwards, from the nares to the pharynx. Towards the anterior opening may be observed the superior orifice of the 

Bonks. — <i 



42 

anterior palatine canal. The internal wall, or septum narium, which extends from the roof to the floor of the cavity, is flat, 
nearly vertical, (the deviation, if any, being usually to the left side,) and composed of the perpendicular plate of the ethmoid 
bone, the vomer, and the nasal cartilage. The external wall is formed by the ethmoid, superior maxillary, os unguis, inferior 
j , and palate bones. The posterior and inferior parts of this surface are marked by a number of inequalities, whilst the 
superior and anterior are comparatively even. In the latter situation may be observed, first, the smooth surface just mentioned; 
and, secondly, passing downwards and backwards, three, and frequently four, arched and convoluted bones, (spongy bones,) 
beneath which are grooves (meatus) leading from before backwards. The superior spongy bone is much shorter than the others : 
li>n>;tth it is the superior meatus, into which will be found opening, anteriorly, a foramen from the posterior ethmoidal cells, and, 
posteriorly, the spheno-palatine foramen. The middle spongy bone overhangs the middle meatus, which communicates with the 
anterior ethmoidal cells ; one of these curves forwards and upwards, and is continuous with the frontal sinus ; more posteriorly 
is situated the opening of the maxillary sinus. The inferior meatus situated below the inferior spongy bone, between it and the 
floor of the nasal cavity, is necessarily longer than the others; it presents anteriorly the orifice of the nasal canal. 

Tfir Frontal, Sphenoidal, and Maxillary Sinuses. — The frontal sinuses correspond with the superciliary eminences of the 
frontal bone. Of considerable size in the adult, but varying in different individuals, they are not at all developed in the foetus. 
They are divided into two, sometimes three compartments. 

The sphenoidal simises, two in number, are placed within the body of the sphenoid bone ; these also cannot be said to exist 
in infancy. They are separated by a partition. Above, behind, and on each side, they are bounded by the body of the sphenoid 
bone, and in front by two small spongy bones, (cornua sphenoidalia.) 

The maxillary sitius (antrum Highmori) is a large excavation in the body of the superior maxillary bone. It appears at an 
earlier period than any of the other sinuses, the developement commencing about the fourth month of foetal life. Its form is irre- 
gularly pyramidal, the base being towards the nasal cavity, the apex corresponding with the malar tuberosity. Superiorly, it is 

PLATE XXIII. 

Anatomy of the os innominatum. 

Fio. 1. The os innominatum of the left side: after Cheselden. 

No. 1. The ilium ; its external or convex surface. 2, 2. The superior curved line of the ilium. 3, 3. The inferior curved line. 4, 4. 
That part of the surface of the bone from which the gluteus medius arises. 5, 5. The rough surface from which the gluteus ma'xi- 
mus arises. G, 6. The surface for the origin of the gluteus minimus. 7. The rough surface which gives origin to one head of the 
rectus muscle. 8, 8. The superior part of the lip of the acetabulum, which forms the inferior boundary of the ilium. 9, 9. The 
crest of the ilium. 10. Its anterior superior spinous process. 11. Its posterior superior spinous process. 12. The notch from 
the upper part of which the sartorius muscle arises. 13. The anterior inferior spinous process. 14. The posterior inferior spinous 
process. 15, 15. The great sacro-ischiatic notch. 16. The spine of the ischium. 17. The lesser sacro-ischiatic notch. 18. The 
body of the ischium. 19, 19. The posterior part of the lip of the acetabulum, which is formed by the ischium. 20. The tuberosity 
of the ischium. 21. The facet upon this tuberosity which gives origin to the semi-tendinosus muscle and the lon<r head of the 
biceps. 22. The facet which gives origin to the semi-membranosus muscle. 23. The ramus of the ischium. 24. The body of 
the os pubis. 25 The crest of this bone. 26. The spine, or tuberosity of the os pubis. 27. The angle of the bone. 28. The 
edge of the articular surface of the os pubis. 29. The rough surface immediately beneath the angle from which the tendon of the 
adductor longus muscle arises. 30. The ilio-pectineal line. 31. The ilio pectineal eminence. 32. The anterior portion of the lip 

5 ThTtJLTo Til Vn ° S 'r ; S ' 33 - J, 6 n ° tCh " the 3CetabU,Um - 34 < 34 ' The articular «»*«» * «»e acetabulum 
biul or oTmen 3~ Th I f^ l"* ^ ^ ^^ ° f M ° f the il[ ^™^ -'-ulation. 36. The 

F,c 2 ™ ° « I ?l *"T T n tbe Und6r SUTfaCe ° f Ae ° S P ubis which S ives P ass ^e to the obturator vessels. 

Fig. 2. The os innominatum of the right side, seen upon its internal aspect : after Cheselden 

No. 1. The concavity of the ilium, which lodges the iliacus muscle. 2, 2. The crista ilii \ Tho o . • 

4. The posterior superior spinous process. 5. The anterior inferior spiLusToce 6 tI notch b't '"'T ^^ ^^ 
processes. 7. The posterior inferior spinous process 8 Thp ili„I P betWee " the anter '° r Spln0US 

10, 10. The i.io-pecLal line. II, U. The arc L po'rtion o IZT FT? , *" ^ UPP<?r n, "* in ° f ^ aCetabU,Um - 
portion of the bone, which is connected w th tl e acrum 2 m ,' amCUlateS ^ lhe 8aCTUm - 12 ' "■ The ""«* 

ireat sacro-ischiatin notch. 15. Th s P £ h Sum" "^'f--- ^-ents. * The ischium. 14, 14. The 
ischium. 18. The border of the tuberosity of ,h i c m to wh ch * T "T^^T "^ l7 " The ^^ ° f the 

of the ischium. 20. The body of the os pubis. 2 ts C r es t 22 r? ^f^* h S ament is attached - ^ The »»«• 
.a, surface of the bone. 25. The ramus J the os pubis. T ^^S^T^' * ^ "* * * ^ "^ 

Fig. 3. A portion of the os innom.natum, from which the external tihle of tKo k 

cancellous structure : after Cheselden. ' haS been removed > '« order to show its cellular or 

Fig. 4. The os innominatum of the youno- subject showing ti 1Q m a a 

the ilium, ischium, and os pubis, ancTtriei cartila ZoL L ! 1 f deVelo P ement ° f the bone by three portions, corresponding with 

No. 1. The ilium. 2, 2. The crest of , he ne wh IX * 3Cetabulum : ■*» Cheselden. 

lage connecting these three pieces of the^nc!*" l^T^T . 3 " The »<- *■ The os pubis. 5, 5. The carti- 
the ischium and pubis. 7. The cartilaginous union betwe'en'the 7 F™™ Um ° f the tuberosit y of the ^chiuni, and rami of 

Fig. 5. The os innominatum of a foetus showing *k„ u . •,, vvoraml - 

-tus, showing the bone at a still earlier stage of developement : after Cheselden. 



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43 

enclosed by the orbital plate of the maxillary bone ; and inferiorly by its palate plate : internally, it opens into the middle meatus 
of the nasal cavity by a foramen, which, though it appears very large in the dry bone when separated from its connexions, is in 
the natural state small, being little more than sufficient for the admission of a probe ; this diminution of size is caused by the 
lower edge of the ethmoid, the inferior spongy and the palate bones, and also by a fold of the mucous membrane. 

Analogy between Cranial Bones and Vertebrae. — Anatomists have at all times perceived and recognised the analogy between 
the movable and motionless pieces of the spine — between those of the lumbar and dorsal regions, and those of the sacrum and 
coccyx : in the one, as well as in the other, similar organic elements are observed to exist, variously modified, in order to suit 
special purposes ; but it is only of late years that any adequate attention has been directed to the points of similitude which exist 
between vertebrae, properly so called, and the cranial bones. Many persons who adopt, without hesitation, the terms false or 
pelvic vertebrae, as applied to the sacrum and coccyx, feel a repugnance to use the word false or cranial, as applied to the pieces 
of the skull ; and deny, perhaps without examination, the analogy upon which it is founded, as being unnatural, or far-fetched. 
We have numerous instances of the harmony that subsists between containing and contained parts throughout the economy ; in 
no case is it more striking than in the relation that obtains between the fundamental part of the osseous structure and the central 
mass of the nervous system. The spinal canal is accurately adapted in its different parts to the nervous cord which it encloses. 
In the pelvic region, the canal, at least in the human subject, becomes narrow, as it merely encloses nerves, whilst the body and 
processes take on a particular developement to meet a special purpose, that of forming a basis of support for the rest of the 
column. This seems to result from the working of what may be termed a principle of compensation in the growth, as well as in 
the action of parts; for when one part of a given whole is developed to excess or to a maximum, others will remain at a mini- 
mum or atrophied : thus the spinal canal and the arches are at their minimum in the sacrum and coccyx, for the contained parts 
are there at a low point of developement; but at the opposite end of the column the reverse obtains; the contained parts, viz. 
the central parts of the nervous system, are evolved in the human subject to the greatest extent, and so must the containing parts 
also be. The portion of the osseous system which corresponds with the bodies of the vertebrae can, therefore, hardly be recog- 
nised ; whilst that which is analogous to the arches is expanded so much as to retain but a slight similitude to them. 

If we take the occipital bone, and examine it attentively, we shall readily perceive in it all the elements of a vertebra. The 
foramen magnum is the counterpart of the ring of a vertebra, and has a similar relation to the spinal cord ; the basilar process 
represents the body ; the condyles are true articulating processes ; the rough surfaces external to them, and which give attachment 
to the recti laterales, correspond to the transverse processes ; the vertical ridge extended backwards along the median line, from 
the foramen to the occipital protuberance is, in the human subject, merely a rudiment of a spinal process; but in the dog, bear, 
and badger, it forms a sharp prominence well deserving the name of spine, and the likeness is still more striking in osseous fishes ; 
finally, the broad plates on each side of the spine represent the arches. In this view of the matter, the occipital bone forms the 
first false vertebra of the cranial region. 

In the second cranial piece or vertebra, it must be admitted that the analogies are not so striking ; but when we recollect 
that the cavity of the skull, if examined in the different orders of animals, enlarges in proportion as the brain acquires an increase 
of developement, and that this enlargement attains its maximum in the human subject, we shall at once find sufficient reason to 
expect that the parts corresponding with the vertebral arches should, in this region, be greatly evolved, while the rest are in a 
manner atrophied. The parietal bones, with the squamous part of the temporal and the great wings of the sphenoid, taken to- 
gether, represent the arches, whilst the posterior part of the sphenoid bone (such as it exists in the human foetus before its ossifi- 
cation is complete, and such as it continues permanently in several lower animals) is the counterpart of the body ; the mastoid 
processes of the temporal bones with the glenoid fossae serve as transverse and articulating processes. These, together, form the 
middle cranial piece, which may be termed the spheno-temporo-parietal cranial false vertebra. 

The frontal bone, the ethmoid, and the anterior division of the sphenoid, (which is that part of the body that sustains the 
smaller wings,) form the third vertebra ; the part of the sphenoid just named, together with the crista galli and the perpendicular 
plate of the ethmoid botic, form the body, which is here reduced to a rudimentary state, just as the coccygeal bones are at the 
opposite end of the column, of which it may be considered a repetition. The lateral and expanded parts of the frontal bone are 
the arches, and the external orbital processes may be likened to transverse processes. 

We have here used the term false vertebra as applied to the cranial pieces ; perhaps it would be better to use the word zone, 
as sanctioned by the authority of Cuvier. The passage in which he recognises the principle of developement here indicated, as 
well as the application of it, (which appears to have been first inculcated by Dumeril, and traced in all its details by Geoffroy 
Saint-Hilaire, is as follows: — " Le crane se subdivise comme en trois ceintures, formees — le anterieure par les deux frontaux et 
l'etlimoide, l'iutermediaire par les parietaux et le sphenoide, la posterieure par l'occipital."* 

Man adapted to the erect posture. — Every part of the conformation of the human subject indicates its adaptation to the 
erect position. The feet are broader than those of any other animal proportionally to its size; the tarsal and metatarsal bones 
admit of very little motion ; and the great toe is on the same plane with the others, and cannot be brought into opposition with them. 
The foot is thus fitted to sustain the weight of the body, but not to grasp or seize objects presented to it. The hands, on the con- 

* Rcgne Animal, torn. i. p. 63. 



44 

though so well adapted for these purposes, are ill calculated for affording support ; so that man is truly "bimanous" and 
I."" The tibia rests perpendicularly on the astragalus, and the os calcis projects backwards for the purpose of increasing 
the base, and also of lengthening the lever to which the strong muscles of the calf of the leg are attached. The whole extent of 
metatarsus, and phalanges, in man, rests on the ground, which does not obtain even in apes, the end of whose os calcis 
is somewhat raised, so as to form an acute angle with the bones of the leg. In dogs and digitated quadrupeds, the carpus and 
firsus are considerably elevated from the ground, so that the body rests on the toes ; and in the horse, and other solid-hoofed ani- 
the third phalanges only rest on the ground, the os calcis being raised nearly to the perpendicular direction. 
The femur, placed securely beneath the pelvis, affords a firm support during progression. The great breadth of the pelvis 
(o enlarge the base on which the trunk rests ; and this is farther increased by the length of the cervix femoris. This 
peculiarity in the neck of the femur renders it necessary that the body of the bone should incline inwards, in order that its axis 
should approach the central line, and so support the centre of gravity. If its articular head be viewed in profile, it will be observed 
thai the cartilaginous coating is distributed for the most part on its upper and inner aspect, showing its adaptation as a pillar of 
.support in the erect position. 

The bones of the pelvis in the human subject are distinguished from those of other animals by some marked peculiarities. 
The sacrum is remarkably broad and expanded, so as to form a firm support for the spinal column which rests upon it ; its lower 
part is curved and articulated with the coccyx, so that both incline forwards and enclose the pelvic cavity, constituting a support 

PLATE XXIV. 

Bones of the lower extremity. 

Fig. 1. Femur of the right thigh, seen upon its anterior aspect : after Cheselden. 

No. 1. The shaft of the bone. 2. Its head. 3. The indentation on the head of the femur for the insertion of the ligamentum teres. 4. 
The neck of the bone, somewhat fore-shortened. 5. The trochanter major. 6. The rough surface for the attachment of the tendon 
of the gluteus minimus muscle. 7, 7. The anterior inter-trochanteric line. 8. The trochanter minor. 9, 9. Foramina upon the 
neck of the bone for the passage of nutrient vessels. 10. The internal and longer condyle of the femur. 11. The tubercle which 
gives attachment to the tendon of the adductor magnus muscle. 12. The tubercle for the attachment of the internal lateral ligament 
of the knee-joint. 13. The external condyle. 14. The tubercle for the attachment of the external lateral ligament of the knee-joint. 
15. The groove for the tendon of origin of the popliteus muscle. 16. Foramina for the passage of nutritious vessels into the can- 
cellous structure of the lower extremity of the femur. 

Fig. 2. The left femur, seen upon its posterior surface : after Cheselden. 

No. 1. The shaft of the bone. 2. Its head. 3. The depression for the insertion of the ligamentum teres. 4. The neck of the femur. 
5. The trochanter major G. A part of the surface for the attachment of the tendon of the gluteus medius. 7. The linea quadrati, 
tor the attachment of the quadratus femoris muscle. 8. The posterior inter-trochanteric line. 9. The trochanter minor. 10 10 
rhe trochanteric or digital fossa 1111. The line leading from the base of the greater trochanter to the linea aspera, for the attach- 
ment of the gluteus max.mus. 12. The ridge for the attachment of the upper part of the adductor magnus muscle. 13, 13 The 
line passing down from the anterior intertrochanteric line to the linea aspera, for the attachment of the pectineus muscle 14, 14. 

external condyle 17, 17. I he con inuat.on of the internal l,p of the linea aspera down to the internal condyle. 18 A slight groove 
on the bone, at which the internal p of the linea aspera is deficient f-hic «™™ „ * *u * , g g 

passage through the tendon of the adductor magnus T 9 "l of tn Im which^f T? Tl * ^ P ° int ° f kS 

space 20 The external conHvlp 91 Th« » i i r I " C 6 0t the tem " which forms p art o f the floor of the popliteal 

.intai e£ e Tr^i Z'^z^it^z^:^ rasr ? r r joint "vs 

tendon of the adductor magnus muscle. 25. Foramina for the transmission If Tv T ' mSertI ° n ° f ^ 

inferior extremity of the b»e. 26. The inter-condyloid Lsa lranSmiSS1 ° n ° f """"P" ~ i" *> the cancellus structure of the 

Fig. 3. Vertical section of the shaft of the femur of a young subject: after Cheselden 

No. 1. The head of the bone. 2. The osseous centre by which the cartila™ n f fk„ i, j c u , ... 

The trochanter major, consisting of cartilage without any 2 „ S 4 4 T e r "? *"" ". T" ^^ **> ^ 3 " 
diaphysis of the bone. 5, 5. The cancellus structure of the upper extrem it I h 7 u ^"T ''T™ ^ 6piphySiS ^ 
shaft of the diaphysis of the bone. 7, 7. The medullary canal 8 Th n P yS ' S ' 6 ' * The denSe StrUCtUre ° f " ie 

physis. 9. The epiphysis of the lower extremity of the b ne ,0 , TtsVn Stn ' ClUre ° f tHe ] ° Wer """^ ° f the dia " 

F,g. 4. The bones of the left lower extremity of a foetus- showiTtri, ! \ Ite cartl ' a ?» n ° US P° rt '°n- H, 11. Its ossifying centre. 

No. 1. The superior epiphysis of the femur! as yT^Z^rS^l ^3^ , «. • 

patella, in the state of cartilage. 5. The superior epiphysis of he t ° 6 Th 7^ , 3 ' ^ ***** •&**+• 4 ' The 

8. The superior epiphysis of the fibula. 9. The diaphysis of the fibu Ta' ^ d ^ .* '^ ^ 7. The inferior epiphysis. 

Fig. 5. A front view of the patella of the left leg: after Cheselden n0 '' eP ' PhyS1S - 

Xo. 1. The upper border of the bone. 2. Its inferior part or apex 

Fig. 6. The patella, seen upon its articular surface: after Cheselden. 

No. I. The upper border. 2. The apex 3 The o-l f 

articulation with the external condyle of 'the 'femur"" ' S " dce ' t0 wh | ch the ligamentum patellae is attached. 4. The surface for 

F,o. r. Section of the pate lla, showing^ J^llTIin.t J ^ * arti ° Ulation WUh the inter " al ^^ 

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45 

for the viscera when pressed down by muscular action. If a different arrangement of these bones obtained — if they were 
continued downwards in a straight line, they would project beyond the ischia and render the sitting posture irksome or 
impossible. 

The spinal column, which is supported on the pelvis, is peculiarly adapted to the erect attitude. Its pyramidal form and 
enlarged base fit it to sustain the superincumbent weight ; and by means of the different curvatures which it presents, a consider- 
able range of motion is allowed to the trunk, the centre of gravity being still supported within the base. The form of the thorax- 
is also peculiar. Shallow and compressed from before backwards, it is broad and expanded from side to side ; by which means 
the preponderance of the trunk forwards is considerably lessened. The sternum, though broad, is very short, so that a consider- 
able space intervenes between it and the pubes, which is occupied solely by muscular parts. But in quadrupeds, the thorax is 
compressed and flattened laterally, becoming gradually narroAver towards the sternum, which is prominent and keel-shaped, so 
that the breadth from this latter bone to the spine is much greater than that from side to side. This conformation, together with 
the absence of clavicles in true quadrupeds, enables the anterior extremities to approach closely together, and fall perpendicularly 
downwards beneath the trunk, so as to give it a steady support. The sternum is elongated in these animals, and the ribs pass 
from the spine to that bone so directly, without making any angle, that they approach near to the crista of the ilia, and thereby 
increase the extent of firm support necessary to sustain the weight of the viscera. Even with these advantages, the muscles of 
the abdomen would be inadequate to the support of its contents, were they not assisted by a layer of elastic substance, which is 
placed over their entire extent, and which of itself marks their destination for the prone position. 

Though the upper and lower extremities present several points of similitude, they yet may be contrasted so as to show that 
they are adapted to totally different purposes. It is quite obvious that the scapula and os innominatum, the humerus and the 
femur, the bones of the fore-arm and those of the leg, the hand and the foot, are respectively constructed on the same plan ; but 
the differences which they present indicate a difference of function. 

The scapulas, placed on the supero-posterior part of the trunk, are borne off by the clavicles ; their glenoid cavities are 
directed forwards and outwards, so that the arms, which are, as it were, appended to them, are fitted to enjoy a considerable 
degree of motion in the anterior and lateral directions. But in true quadrupeds the glenoid cavities look downwards, and are 
approximated closely together, so that the thoracic limbs, which are articulated with them, descend beneath the fore part of the 
trunk ; and, as they are thus calculated to support its weight, they possess little lateral motion. The glenoid cavity in man is 
quite shallow, so that the globular head of the humerus is merely applied to its surface ; but the acetabulum is a deep cup-like 
cavity, indicating a quite different destination in the two joints. The breadth of the articular surfaces of the knee-joint, and the 
peculiar conformation of the ankle-joint, as contrasted with the elbow and wrist, are abundantly sufficient to show that fixity and 
strength have been designed in the one, mobility in the other. This difference is, if possible, more strongly marked in the con- 
formation in the hand and foot : the latter, as has been already observed, being intended to support the body, is placed at right 
angles beneath the leg ; the former is continuous with the line of direction. of the fore-arm, otherwise it could not be guided with 
sufficient precision to the different objects which it is intended to seize. The tarsal bones are large, firm and strong ; those of the 
metatarsus are also thick and large, and placed all in a line. That which supports the great toe being the stoutest of all, and 
almost immovable, ranges with the others. But the metacarpal bones are quite differently disposed ; that which supports the 
thumb admits of considerable motion in every direction, so as to perform a complete circumduction, and is placed so much out of 
line with the others that it can be opposed to them, as in grasping different objects. The hand and foot may be considered as 
divisible each into two parts, differing in their degrees of mobility, viz. the digital phalanges, and the row of bones which sustains 
them. The movable phalanges of the hand are as long as the carpal and metacarpal bones taken together; but in the foot, they 
are not a third of the length of the tarsal and metatarsal bones. 



PLATE XXV. 

The ligaments of the pelvis and hip-joint. 

Fig. 1. The left side of the pelvis, showing its ligaments and the capsular ligament of the hip-joint, seen from the front. 

No. 1. The last lumbar vertebra. 2, 2. The transverse processes of this vertebra. 3, 3. The front surface of the sacrum. 4. The 
anterior common ligament of the vertebral column. 5, 5. The intervertebral substance between the body of the last lumbar vertebra 
and the base of the sacrum. 6. The anterior sacro-coccygean ligament. 7. The internal and concave surface of the ilium, or iliac 
fossa. 8, 8. The ilio-pectineal line. 9. The internal surface of the ischium. 10. The ilio-lumbar ligament. 11. The sacro- 
vertebral ligament. 12, 12. The anterior sacro-iliac ligaments. 13, 13. The anterior surface of the ossa pubis. 14. The anterior 
pubic ligament. 15. The superior pubic ligament. 16. The inferior or sub-pubic ligament. 17. The ramus of the pubis and 
ischium. 18. The tuberosity of the ischium. 19. The obturator ligament or membrane. 20. The aperture left between the upper 
border of this ligament and the os pubis for the passage of the obturator vessels and nerve. 21. 21. The capsular ligament of the 
hip-joint. 22. A ligamentous band which strengthens this capsule, — the ilio-femoral ligament. 23. The border of the transverse 
ligament of the acetabulum. 24. The notch in the acetabulum for the transmission of vessels and nerves, 25. The head of the 
lemur. 26. The great trochanter. 27. The lesser trochanter. 



46 

part of the osseous system of man affords more striking evidence of his adaptation for the erect posture than the cranium. 
, L the summtt of the vertebral column, the line of its base forms a right angle with that of the column Uself, winch thus 
affords it a firm support. The condyles, or points of articulation, are situated very near the centre of its base being, however, a 
i nearer to the occipital protuberance than to the anterior surface of the jaws ; by this arrangement, very little active power „ 
uned to maintain it in afrilBrU- In other animals the condyles are placed much further back ; so that, instead o res mg on 
,, Znn, the skull is, as it were, appended to its extremity, and is sustained by an elastic substance hgamentum nuchee ) winch 
is attached by one extremity to the spinous processes of the vertebra, and by the other to the ocapt al protuberanc . 1 he head, 
as has been already observed, is composed of two parts, the cranium and face; the one being intended to contain the bran, -the 
material instrument of the mind ; the other to enclose the organs of sight, smell, and taste. The more the organs of smell and 
taste are developed, the greater is the size of the face, and the greater its relative proportion to the cranium. On the contrary, the 
larger the brain, the greater must be the capacity of the skull, and the greater its proportion to the face. On this principle, a large 

Fig. 2. The ligaments of the pelvis and the capsular ligament of the hip-joint, seen from behind. 

No. 1. The last lumbar vertebra. 2, 2. The posterior surface of the sacrum. 3, 3. The continuation of the supra-spinous ligament 
of the vertebrae. 4. The posterior sacro-coccygean ligament. 5. The tip of the coccyx. 6. The ilium, seen upon its external and 
convex surface. 7, 7. The crest of the ilium. 8. The posterior and superior spinous process of the ilium. 9. The ilio-lumbar 
ligament. 10. The sacro-vertebral ligament. 11, 11. Posterior sacro-iliac ligaments. 12. The posterior part of the body of the ischium. 
13. The great sacro-ischiatic foramen. 14. The lesser sacro-ischiatic foramen. 15. The tuberosity of the ischium. 16, 16. The 
great sacro-ischiatic ligament. 17. The spine of the ischium, to which the lesser sacro-ischiatic ligament is attached. 18. The 
upper extremity of the femur. 19. The capsular ligament of the hip-joint. 20. The greater trochanter of the femur. 21. The 
lesser trochanter. 

lie 3. A side view of the pelvis, seen from its external aspect, and showing its ligaments. 

No. 1. The external surface of the ilium. 2, 2. The posterior surface of the sacrum. 3. The coccyx. 4. The ischium. 5. Its spine. 
6. Its tuberosity. 7, 7. The great sacro-ischiatic ligament. 8, 8. The lesser sacro-ischiatic ligament. 9. The great sacro- 
ischiatic foramen. 10. The lesser sacro-ischiatic foramen. 11. The acetabulum. 12, 12. The cotyloid ligament of the articula- 
tion of the hip-joint. 13. The transverse ligament. 14. The os pubis. 15. The ramus of the pubis and ischium. 16. The 
obturator membrane. 

Fig. 4. A side view of the pelvis, seen from within. This view has been made by means of a section carried through the middle line 
of the cavity, and dividing the sacrum and coccyx behind, and the symphysis pubis in front. 

No. 1. The inner surface of the ilium, or iliac fossa. 2, 2. A section of the last lumbar vertebra. 3. Its transverse process. 4, 4. Sec- 
tion of the sacrum. 5. Section of the coccyx. 6. The lower part of the spinal canal. 7,7. The sacral canal. 8. The interverte- 
oral ligament connecting the body of the last lumbar vertebra with the superior articular surface of the sacrum. 9. The interspinals 
Sgament between the spinous process of the last lumbar vertebra and the superior spinous process of the sacrum. 10. The ilio- 
lumbar ligament. 11, 11. The ilio-pectineal line. 12, 12. The anterior surface of the sacrum. 13. The anterior sacro-iliac liga- 
ments. 1 I. 'I'lic internal surface of the ischium. 15. The spine of the ischium. 16. The tuberosity of the ischium. 17. The 
gnat sacro-ischiatic foramen. 18. The lesser sacro-ischiatic foramen. 19. The lesser sacro-ischiatic ligament. 20, 20. The great 
sacro-ischiatic ligament. 21. That portion of the great sacro-ischiatic ligament which is attached to the inner border of the tuberosity 
of the ischium. 22. The ramus of the pubis and ischium. 23. The internal surface of the os pubis. 24. The articular surface of 
the pubis, which unites with its fellow of the opposite side at the symphysis. 25. The obturator membrane. 26. The aperture 
between the upper border of the obturator membrane and the bone which gives passage to the obturator vessels and nerve. 

Fig. 5. The ossa pubis and their articulation, seen from the inner aspect of the pelvis. 

Nos. 1, 1. The inner surface of the ossa pubis. 2, 2. The ramus of the pubis and ischium at each side. 3, 3. The tuberosity of the 
ischium at each side. 4, 4. A part of the acetabulum at either side. 5, 5. The transverse ligament of the acetabulum. 6, 6. The 
notch of the acetabulum, converted into a foramen by the transverse ligament. 7, 7. The obturator membrane. 8, 8. The opening 
for the passage of the obturator vessels and nerve. 9. The symphysis pubis; its internal ligament. 10. The superior pubic liga- 
ment. 11. The sub-pubic ligament. 

Fig. 6. A section carried through the anterior part of the bodies of the ossa pubis, in order to show the fibrous tissue which connects the 
articular surfaces of these bones. 

Nos. 1, 1. The cut surface of the pubic bones. 2. The fibrous tissue connecting the articular surfaces of the ossa pubis. 

Fig. 7. The capsular ligament of the hip-joint, and the bones entering into the formation of this articulation. 

No. 1. The anterior inferior spinous process of the ilium. 2. A part of the os pubis. 3. A part of the ischium. 4. The great 
trochanter of the femur. 5, 5. The capsular ligament of the hip-joint. 6, 6. The ilio-femoral ligament. 7. The notch in the 
acetabulum for the passage of the vessels and nerves of the hip-joint. 8. The upper part of the shaft of the femur. 9. The lesser 
trochanter. 

Fig. 8. The hip-joint laid open, and the capsular ligament removed : from Cheselden 

No. 1 A part of the ilium 2 The anterior and inferior spinous process of the ilium. 3, 3. The lip of the acetabulum. 4. The cup 
of the acetabulum 5. The fossa of the bottom of the acetabulum. 6, 6. The cotyloid ligament. 7. The transverse ligament. 
8, 8. The hgamentum teres. 9. The head of the femur covered with cartilage. 10. The neck of the femur. 11. The trochanter 
major 12 The upper part of the shaft of the femur. 13. The ramus of the pubis and ischium. 14. The body of the os pubis. 
\o. 1 he obturator foramen. J ' 

* Lawrence on the Characters of the Human Head, passim. 






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47 

cranium and a small face indicate a large brain with a restricted developement of the sense of smell and taste ; but a small cranium 
and a large, face mark an opposite conformation. The character and nature of animals is determined by the degree of energy 
with which their different functions are performed ; they are guided and impelled by some leading propensity or disposition ; and 
as the cranium and face bear to the brain and organs of sense the relation of containing and contained parts, the study of their 
relative proportions is one of great interest to the naturalist, inasmuch as they serve as indices of the faculties, instincts, and capa- 
bilities of different individuals as well as of classes. 

Several methods have been suggested for determining the proportion of the cranium to the face ; the simplest is that of 
Camper. If a line be drawn upwards from the side of the chin over the most prominent part of the forehead, it will form an 
angle with a horizontal line drawn backwards over the external auditory foramen from the margin of the anterior nares ; the size 
of the angle will indicate the degree of developement of the cranium and brain, as compared with that of the face and organs of 
sense. In the crocodile these lines are so nearly coincident, that there is scarcely any appreciable angle. 

In the Horse it measures* ------ 23° 

Ram 30 

Dog 35 

Ouran-outang - - - - - - - - 56 to 60 

European adult -------85 

PLATE XXVI. 

The bones and ligaments of the leg. 

Fig. 1. The tibia and fibula of the left leg in their articulated position: after Cheselden. 

No. 1. The head of the tibia. 2. Its spinous process. 3. The surface of the head of the bone, for articulation with the inner condyle 
of the femur. 4. The external tuberosity of the tibia. 5. The internal tuberosity. 6. The tubercle of the tibia for the attachment 
of the ligamentum patellae. 7. A smooth surface immediately above the tubercle, corresponding with the situation of a bursa 
mucosa. 8, 8. The subcutaneous surface of the shaft of the tibia. 9, 9. The concave external surface, which gives attachment to the 
tibialis anticus muscle. 10. The ridge for the attachment of the interosseous membrane. 11. The surface behind this ridge, which 
gives attachment to one head of the tibialis posticus muscle. 12. The inferior extremity of the tibia. 13. The internal malleolus 
of the tibia. 14. The upper extremity of the fibula. 15. That portion of the head of the fibula which gives attachment to the 
external lateral ligament of the knee-joint. 16, 16. The shaft of the fibula; its external surface. 17, 17. The internal surface of 
the fibula. 18. The lower extremity of this bone, forming the external malleolus of the ankle. 19, 19. The subcutaneous surface 
of the external malleolus. 

Fig. 2. The tibia of the right leg, seen upon its posterior surface: after Cheselden. 

No. 1. The head of the bone. 2. The spinous process of the tibia. 3. The surface of articulation for the inner condyle of the femur. 
4. The surface of articulation for the external condyle of the femur. 5. The inner tuberosity of the tibia. 6. The fossa upon this 
tuberosity for the insertion of the tendon of the semimembranosus muscle. 7. The outer tuberosity of the tibia. 8. The smooth 
surface on this tuberosity for articulation with the head of the fibula. 9. The oblique line of the tibia. 10. The surface above the 
oblique line for the attachment of the popliteus muscle. 11, 11. The posterior surface of the shaft of the tibia. 12. The nutritious 
foramen of the tibia. 13, 13. The interosseous line upon the external aspect of the tibia. 14. The surface of the tibia which gives 
origin to the internal head of the tibialis posticus muscle. 15, 15. The external surface of the shaft of the tibia, corresponding with 
the anterior muscles of the leg. 16. The lower extremity of the tibia. 17. The surface at the lower extremity of the tibia for 
articulation with the fibula. 18. A slight groove for the support of the tendon of the flexor longus pollicis. 19. A deeper groove 
for the tendons of the tibialis posticus and flexor longus digitorum. 20. The internal malleolus of the tibia. 21. The surface 
which articulates with the astragalus. 

Fig. 3. The fibula of the right leg, viewed upon its external side : after Cheselden. 

No. 1. The upper extremity or head of the bone. 2. The spine which gives attachment to the tendon of the biceps muscle. 3. The 
rough surface which gives attachment to the external lateral ligament of the knee-joint. 4, 4. The external surface of the shaft of 
the fibula. 5, 5. A part of the posterior surface of the shaft of the fibula. 6, 6. The lower extremity of the bone; its subcutaneous 
surface. 7. The point of the external malleolus. 8. The anterior or sharp border of the external malleolus. 9. The posterior 
border, deeply grooved for the passage of the tendons of the peronei muscles. 

Fig. 4. A view of the articulating surface of the head of the tibia. 

No. 1. The spinous process of the tibia. 2. The fossa in front of this process for the attachment of the anterior crucial ligament. 

3. The fossa behind this ligament for the posterior crucial ligament. 4. The articulating surface for the internal condyle of the 
femur. 5. The articular surface for the external condyle of the femur. 

Fig. 5. The inferior articulating surface of the tibia, seen from beneath. 

No. 1. The anterior border of this extremity of the bone. 2. The surface which articulates with the astragalus. 3. The malleolus of 

the tibia. 4. The external surface of this malleolus, which articulates with the side of the astragalus. 5. The border of the surface, 

which articulates with the fibula. 
Fig. 6. The tibia and fibula of the right leg, with their connecting ligaments : after Bourgery. 
No. 1. The spinous process of the tibia. 2. The ligamentum patella;. 3, 3. Portions of the capsular ligament of the knee-joint. 

4. The shaft of the tibia. 5. The shaft of the fibula. 6. The articulation between the head of the fibula and the external tubero- 
sity of the tibia. 7, 7. The interosseous membrane. 8. The aperture in the upper part of the interosseous membrane for the 
passage of the anterior tibial vessels. 9. The anterior tibio-fibular ligament of the inferior articulation between these two bones. 

* Cuvier, Lecons d'Anatomie Comparce, torn. ii. p. 8. 



18 

Thus we find man at the top of the scale of animated beings, distinguished from all the rest as well by his external oonforma 
non as l.y his internal organization. When the mind has passed in review the many links of the chain which connects the lowest 
with the highest— the mere animated dot, with man, the lord of the creation, it cannot fail to be struck with astonishment at the 
immense chasm which separates them. Yet, when each link of the chain is compared with that which precedes and follows it, 
the transition from the one to the other is found to be so gradual as to be almost imperceptible. So easy are the steps of ascent 
from the organization of the higher orders of the quadrumana, up to the human species, that even Linnaeus felt it difficult to 
a-i.'ii the specific characters by which man is distinguishable from all others; but any doubt that may have existed on this 
suhjeet has been long since removed. The physical and moral attributes of man are universally recognised as sufficient to elevate 
him much further from the higher mammalia than these are from the classes beneath them; and in the opinion of Cuvier,* he 
should be considered not merely as a distinct species, but even as forming a separate order by himself. Whether, then, with the 
zoologist, we consider the physical conformation of man as compared with that of other animals, or, with the moralist, reflect on 
his mental powers and high destination, we can scarcely refrain from saying, with the poet, 

Sanctius his animal mentisque capacius altae 
Deerat adhuc, et quod dominari in caetera possit, 
Natus est homo. 

PLATE XXVII. 

The ligaments of the knee-joint. 

Fir,. 1. The ligaments of the front of the knee-joint: after Bourgery. 

No. 1. The lower part of the femur. 2. The tibia. 3. The fibula. 4. The patella. 5. The tendon of the rectus muscle. 6. The 
ligamentum patellae. 7, 7. The internal lateral ligament. 8. A ligamentous band passing inwards from the inner border of the 
patella, and expanding over the synovial membrane. 9. A similar band proceeding from the outer border of the patella. 10. The 
external lateral ligament. 11. The upper part of the interosseous membrane. 12. The aperture of transmission for the anterior 
tibial artery. 

Fig. 2. The ligaments of the knee-joint, seen from behind: after Bourgery. 

Nos. 1, 2, 3. The femur, tibia, and fibula. 4, 4. The posterior ligament,— ligamentum posticum Winslowii. 5, 5. Openings in this 
ligament for the passage of vessels and nerves. 6, 6. The two heads of the gastrocnemius muscle. 7, 7. The internal lateral 
ligament. 8, 8. The two external lateral ligaments. 9. The tendon of origin of the popliteus muscle. 10. The tendon of the 
semimembranosus muscle, cut short. 1 1. The posterior ligament of the peroneotibial articulation. 12. The interosseous ligament 

* io. J. 1 he ligaments of the knee, seen upon the outer aspect of the joint : after Bourgery. 

Nos 1,2,3 The femur, tibia, and fibula. 4. The patella. 5. The common tendon of the quadriceps extensor muscle. 6 The 
l.gamentum patella,. 7, 7. Bands of ligament which strengthen the anterolateral portions of the articulation. 8, 8. The synovial 

Z miTs' 12 Th l7r ei cVT l Ug *TL 10 - The Sh ° rt 6Xternal ,ateral ]igameDt - "' The external head ° f t^e gas- 
trocnemius. 12. The tendon of the biceps. 13. The interosseous membrane. 

Pie. 1. Th,. ggaments of the knee, seen upon the inner aspect of the joint: after Bourgery 

Nos 1, 2, 3. The femur, tibia and fibula. 4. The patella. 5. The tendon of the rectus muscle. 6. The Momentum patella; 7 A 

l r^^T^:Z^^^' 8 ' 8 ' Theimernal ,3teral "— ^ - -maSof ihe^ 

N^eStX.^ 

mterna, surface of J patell , , The mucous^ "ft T^^ ^^ "~ d "* — ** *' *> 

^^ZZirtirZZ^ br °" ght int ° ^ ^ *—■ "* a P- " * *»— -brane ; the 
No. 1. The external condyle. 2. The internal r. nn ^l q o tu ■ i 

upwards. 5. The anterior cru ia H^meL 6 6 The n si Syn ° Vla "! embrane > tU ™ d back " 4 ' The mucous ligament, lifted 
transverse ligament. 9. The *L °ToL fibula f Th eT T J'FTv "^ Th — »— fibro-carti.ages. 8. The 
meat. .3. The tendon of the biceps. '" part ° f the ^S^entum patell*. 12. The interosseous liga- 

G ' H^«; Bo^n- ^ ° f ^ knee - j ° int ' *"*■ ^ —»■" ^re-cartilages, and the inferior attachments of the crucial 

No. 1. The anterior part of the head of the tibia 2 2 Th P pv< i 

cartilage. 4. The anterior crucial ligament 5 The „ ! * le . Sem,,unar fibro-cartilage. 3, 3. The internal semilunar fibro- 
side of the joint. 7. The head of the fibula' 8 8 vlTTl ° ]l S a ™nt. 6. A part of the coronary ligament on the outer 

Fig. 8. A vertical section of the knee-joint upon the middle 1 1 h '"T kteral ]igmmU 

after Bourgery. P middle lme ' show ">g the reflections of the synovial membrane of the articulation : 

No. 1. The femur. 2. The tibia. 3. The fibula. 4. The patella * Tl. ♦ , e , 

mentum patellar. 7. The bursa of the ligamentum patella, ft* ri , quadriceps extensor muscle. G. The liga- 

9. The anterior crucial ligament. 10. The pouch of sv " ' 1 artlcular mass of f a* situated behind the ligamentum patell*. 

muscle and the front of the lower part of the femur ™,™ mh ™ ne situated betw *en the tendon of the quadriceps extensor 
"igament. ■ "• "« mucous ligament. 12. The alar ligament. 13. The posterior 

* Regne Animal, torn. i. p. 81. 



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49 

The Teeth. — The adult human subject is furnished with thirty-two teeth, sixteen in each jaw, arranged so that eight are 
placed on each side of the symphysis, in*the upper and lower maxilla?. To facilitate their description, it is usual to consider a 
tooth as divisible into its crown, or that part projecting externally; the root, or that contained within the alveolus; and the neck, 
or part intermediate between the two. The root and central part of each tooth are composed of dense and hard osseous matter ; 
and the projecting part, or crown, is, moreover, encased by a layer of white and excessively hard laminated substance, called 
enamel; at the superior and lateral parts of the crown the layer of enamel deposited upon it is thick, but gradually becomes thin 
at the neck, and disappears at the commencement of the root. The root and body of each tooth present a cavity, lined by a 
membrane, (pulpa dentis,) on which the nutritious vessels and nerves ramify, after having entered through the foramina in the 
apices of the roots. 

The teeth differ in size, form, manner of insertion, and mode of action, so that they are divisible into four sets, each of which 
has received a particular denomination, viz. incisores, cuspidati, bicuspidati, and molares. 

The incisor or cutting teeth, (dentes incisores,) four in number in each jaw, are placed at the fore part of the mouth, forming 
the convex prominent part of the dental arch ; their projecting part is wedge-shaped, the anterior and posterior surfaces being 
compressed, so that their free border is thin and sharp ; this part of the tooth is convex in front, flat or concave behind, where it 
slopes upwards and forwards from a small elevation, which surmounts the neck. Those in the upper jaw, particularly the central 
pair, are larger than those of the lower. The roots of all are single, elongated, and tapering: the inserted as well as the project- 
ing part of an incisor tooth is wedge-shaped, the former being compressed from side to side, the latter from before backwards. 

The canine teeth (dentes cuspidati, canini) are two in number in each jaw, and come next in order after the lateral incisors. 
In these the projecting part is convex anteriorly, concave and sloping behind, and tapers towards its summit, where it ends in a 
blunted point : the root is longer and sinks deeper into the alveolus than that of any other teeth ; it is single, conical, compressed 
at the sides, and marked by a slight groove, running its whole length from its apex to its summit. This is a trace or a rudiment 
of that division into processes which obtains in the molar teeth. 

The small molar or bicuspid teeth, (dentes bicuspidati,) four in number in each jaw, are so named from usually having a 
divided root. They are intermediate in size as well as in situation between the cuspidati and molares. Their crown, compressed 
laterally where it is in apposition with the other teeth, is rounded on the external and internal sides, so that its depth from with- 
out inwards is greater than that of the incisores or cuspidati, whilst its breadth from side to side is less. The cutting extremities 
present two tubercles, one internal, the other external ; in the lower jaw the internal tubercle is but very slightly prominent. A 
section of the neck presents an oval form ; the root is single till near the apex, where it is usually bifid, particularly in the pos- 
terior bicuspidati ; the groove at its sides is deeper than in the cuspidati. 

The large molar or true grinding teeth (dentes molares) are larger and placed farther back than the others ; the crown, or 
projecting part, is compressed from before backwards, as well as at the sides, so as to assume a cuboid form ; its free surface, 
which is intended for trituration, is surmounted by four tubercles, separated by depressions, which so intersect one another as 
generally to assume a crucical form. There are six molares in each jaw when the set is completed : the first and second are the 
largest of all the teeth, and in the upper jaw are usually furnished with three roots, very seldom with four, whilst in the lower 
jaw there are but two. The disposition of the roots deserves attention. In the upper jaw two of the roots are placed external, 
and parallel in their direction, whilst the third projects inwards from them at a slight angle ; in the lower jaw the roots are placed 
one anterior, the other posterior. The last of these molar teeth are the smallest, and, as they appear at an advanced period of 
life, are named dentes sapientix. The root is often single and tapering, but marked by two grooves, indicating, as it were, a 
tendency to separation ; in the upper jaw we frequently find it bifid, with traces of a still further subdivision. 
The dental formula for the adult is as follows: — incisors f, canine |, bicuspidati f, molares £-. 

What has been here stated applies altogether to the permanent teeth. The temporary or deciduous teeth which precede 
them are fewer in number, being twenty in all when complete ; they are also smaller, and more delicate in their texture. 
The formula for these is thus expressed : — incisors %, canine §, molares <. 

The incisores and cuspidati are supplanted by permanent teeth of the same name : the bicuspid, which do not previously 
make their appearance, occupy the place of the temporary molares, so that the permanent molares will necessarily protrude at 
points farther back. The sockets into which the teeth are inserted are called alveoli ; their form, number, and size being deter- 
mined by that of tlie roots, which they lodge and receive ; the alveolus being divided into two or three pits when the insertion 
of the tooth requires it, and being but a simple tapering fossa when a simple conformation obtains. The texture of the bone 
along the alveolar arches is porous and open, particularly in the transverse plates which separate the alveoli. In the natural 
state each of these cavities is lined by a prolongation of the periosteum, which invests the maxillary bones, and which extends 
into them as far as their apices, where it is reflected on the roots of the teeth so as to form a special investment for them. 

The Thorax.— Into the composition of the thoracic portion of the skeleton enter the sternum and ribs, which are proper and 
peculiar to it, and the vertebra}, which are common to it and other parts. 

The Sternum and Ensiform cartilage.— The sternum is situated in the median line, at the fore part of the thorax : it is flat 
and narrow, but not of equal width in its entire extent, being broad at its upper part, then narrowed somewhat, after which it 
Bones. — 7 



50 

t nnri n ,rm« where it ioins the ensiform cartilage. Its direction is oblique from 
widens a little ; finally it becomes "^^^^ ^aclwards in the dorsal part of the vertebral column, causes a 
downward- and forwards; which, together with f ^^^^ We h J t0 consider successively its surfaces, 
considerable increase in the antero-postenor diameter of the thorax mierioriy 

extremities, and borders. attachment to the aponeurosis of the pectoralis major 

Til.- -uitprinr surface slieht v convex, and subjacent to the sKin, giveb i"*^""' r *■ j 

1 Iil anterior sunace, suguuy ou , j ,• indicating its original division into five pieces. The 

hyoideus and sterno-thyroideus muscles ; inferiorly, to the triangularis sierm. s 

left bv the divergence of the two pleurae, (anterior mediastinum.) 

Tta borders are thick, and marked on each side by seven angular depressions for the reception of the cartilages of the true 
ribs, which rive them a notched or serrated appearance. 

The superior extremity, broad and thick, is slightly excavated from side to side, and presents at each corner a depression for 
the reception of the sternal end of the clavicle. , ^^ . . 

The sternum, in early infancy, is divided into several pieces, but in adult age two only remain distinct. The first division 
of the sternum is larger and (bicker than the other; its form is nearly square; its lateral margins, thin and oblique, present each 
an oblong depression, which receives the cartilage of the first rib ; and at each inferior angle may be observed an articular half 

PLATE XXVIII. 

The bones of the foot in their articulated position and in the fcetal state. 

Fig. 1. The right foot, seen upon its upper surface: after Cheselden. 

No. 1. The superior articular surface of the astragalus. 2. The anterior portion of that bone. 3, 3. The os calcis. 4. The commence- 
ment of the groove in which the interosseous ligament is lodged. 5. The scaphoid bone. G. Its tuberosity. 7. The internal 
cuneiform bone. 8. The middle cuneiform bone. 9. The external cuneiform bone. 10. The cuboid bone. 1 1 , 1 1 . The metatarsal 
bones. 12, 12. The first row of phalanges. 13, 13. The second row of phalanges. 14, 14. The last phalanges. 

Fib. 2. The under surface of the same foot: after Cheselden. 

No. 1. The under part of the os calcis. 2. The posterior tuberosity of the os calcis. 3. The internal tuberosity of that bone. 4. Its 
external tuberosity. 5. The concave surface of the os calcis, which supports the tendons and vessels which pass into the sole of the 
foot. 6. The groove in which the tendon of the flexor longus digitorum muscle plays. 7. The side of the astragalus. 8. The 
rounded head of the astragalus. 9. The under surface of the scaphoid bone. 10. The tuberosity of the scaphoid bone. 11. The 
internal cuneiform bone. 12, 12. The apex of the middle cuneiform bone. 13. The external cuneiform bone. 14. The cuboid 
bone. 15, 15. The groove in this bone for the tendon of the peroneus longus muscle. 16. The metatarsal bone of the great toe. 
17. The tubercle at its base which gives insertion to the tendon of the peroneus longus. 18, 18. The remaining metatarsal bones. 
19. The tubercle on the base of the metatarsal bone of the little toe. 20, 20. The first row of phalanges. 21, 21. The second row 
of phalanges. 22, 22. The last phalanges. 

Fig. 3. The inner border of the left foot: after Cheselden. 

No. 1. The superior articular surface of the astragalus. 2. The lateral surface, which articulates with the inner malleolus of the tibia. 
3. The inner and concave side of the os calcis. 4. The posterior tuberosity of the os calcis. 5. The internal tuberosity of that 
bone. 6. The process which supports the anterior portion of the astragalus. 7. The anterior part of the astragalus. 8. Its articular 
surface. 9. The scaphoid bone. 10. Its tuberosity. 11. The internal cuneiform bone. 12. A smooth facet which gives attach- 
ment to the tendon of the tibialis anticus muscle. 13. The base of the middle cuneiform bone. 14. The metatarsal bone of the great 
toe. 15, 15. The metatarsal bones of the other toes. 16. The first phalanx of the great toe. 17. The last phalanx of the 
same toe. 

Fin. 1. The left foot, seen upon its outer side: after Bourgery. 

No. 1. The superior articular surface of the astragalus. 2. The triangular lateral surface which articulates with the external malleolus. 
3. The anterior portion of the astragalus. 4, 4. The os calcis. 5. Its posterior tuberosity. G. Part of the smooth surface which 
supports the bursa of the tendo Achillis. 7. The external tuberosity of the os calcis. 8. The smooth pulley-like surface against 
which the tendons of the peronei muscles play. 9, The cuboid bone. 10. A notch upon the cuboid, which marks the commence- 
ment ol the groove for the tendon of the peroneus longus muscle. 11. The scaphoid bone. 12. The external cuneiform bone. 13. 

' ,? p * T J""' , H ' U - THe metatarSal b ° neS - 15 - The ,uberosit y at the base ° f *e metatarsal hone of the little toe. 

lb, 16. The first row of phalanges. 17, 17. The second row of phalanges. 18, 18. The last phalanges, 
r is. a. A single toe, showing the four bones which enter into its formation: after Cheselden 
No. 1 The metatarsal bone 2 A smooth surface by which the base of this bone articulates with the adjoining bone. 3. The head of 

the metatarsal bone 4. The first phalanx. 5. Its base. 6. Its head. 7. The second phalanx. 8. The third and last phalani. 
Fig. C. The two sesamoid bones of the metatarsophalangeal articulation of the great toe 
Fig. 7 The foot of a foetus at an early period : after Cheselden. The tarsus is wholly cartilaginous, and the metatarsal hones and 

phalanges only partly developed. b 

Fig. 8. The foot of a fetus at a more advanced period : after Cheselden. 




/■ 'iff 7 




/■/<//< ?H 



//// 6 



Fiff 8 
















51 

notch, which articulates with the second rib. The superior border is hollowed, and at the angles which bound it are the fossae, 
which articulate with the clavicles, as has been already stated; the inferior is straight, and united to the extremity of the 
second piece. 

The second piece, much longer than the first, is marked on its anterior surface by some transverse lines, which indicate its 
original division into separate portions. Both surfaces are nearly fiat. The upper border is narrow, corresponding in breadth 
with the termination of the first bone, with which it is connected by cartilage. The lateral margins present each five notches for 
the reception of the cartilages of the five lower true ribs, and a half notch superiorly, which, with a similar depression in the first 
piece, forms a cavity for the second costal cartilage. The five inferior notches approach one another more closely in proportion as 
they are situated lower down, and part of the last is occasionally made up by the ensiform cartilage. 

The inferior extremity of the sternum, thin and elongated, gives attachment to a cartilaginous appendix, called the ensiform 
or xiphoid (it$o{, a sword ; tt8o 5 ) cartilage, which in most cases remains in the cartilaginous state until an advanced period of life. 
It is sometimes bent forwards, sometimes in the opposite direction, and. sometimes pierced by a hole at its centre. Its form varies 
considerably in different individuals : it gives attachment to the aponeuroses of the abdominal muscles. 

Articulations. — This bone articulates by its sides with the true ribs, — by its upper angles with the clavicles, and by its lower 
end with the ensiform cartilage. When examined at an early period, it exhibits usually eight or nine ossific centres. When sawed 
across, the sternum presents a considerable quantity of loose spongy texture in its interior, with a very thin lamella of compact 
tissue on its outside ; — hence it is very light. 

The Ribs and their cartilages. — The ribs (costse) extend from the dorsal portion of the vertebral column to the sternum, 
forming arches, which enclose the lateral parts of the thorax. They are twelve in number at each side, of which the seven 
superior pairs, which are united by means of cartilaginous prolongations to the sternum, are called sternal or true ribs ; the 
remaining five, which are not prolonged to the sternum, being denominated asternal or false ribs. 

The ribs do not arch uniformly from the vertebral column towards the sternum ; the greater number consist of parts of two 
circles or arches of different diameters, the anterior being much the larger. Thus the rib, directed at first backwards from its 
connexion with the bodies of the vertebrae, reaches and is supported by the transverse process, (which in the dorsal region is 
inclined backwards ;) after leaving the extremity of this process it turns abruptly outwards, and finally is directed forward towards 
the sternum. 

In their length, breadth, and direction, these bones present several varieties. From the first to the eighth their length succes- 
sively increases, whilst from the ninth to the twelfth they gradually decrease, so that the last is very little longer than the first. 

Their breadth, considered in the whole series, diminishes gradually from the first to the twelfth ; but in each rib it is greatest 
towards its sternal extremity. 

As to their direction in reference to the vertebral column, the first forms almost a right angle with it, and the succeeding ones 
gradually incline downwards, so that their anterior extremity is lower than the posterior. The body of all the ribs, except the 
first, is, as it were, twisted on itself, so that their two extremities cannot be made to rest at the same time on a plane surface. 

These bones present two surfaces, two borders, and two extremities. 

The external surface is convex and smooth. The internal is concave, and corresponds with the pleura. 

The superior border, smooth and rounded, gives attachment to the intercostal muscles ; the inferior is marked on its inner 
aspect by a groove, which is commonly said to be for the lodgment of the intercostal vessels, and also gives attachment to the 
intercostal muscles. 

The posterior extremity, somewhat rounded and thicker than the other parts of the rib, and hence denominated its head, 
presents (except in the instances to be presently stated) two articular faces (separated by a slight ridge) which articulate with the 
corresponding small surfaces on the bodies of the dorsal vertebrae ; the head is supported by a narrow round part, or neck, 
terminated externally by a tubercle, which is smooth in one part for its articulation with the transverse process of the lower of 
the two vertebrae to which the head is connected, and rough in the other for the insertion of the posterior costo-transverse 
ligament. 

The anterior extremity is broad, flat, and hollowed at its tip into an oval pit, into which is implanted the costal cartilage. 

Between the tuberosity and the most convex part of the body of each rib is a rough line, marking what is termed its angle. 
The distance of the angle from the tuberosity increases gradually from the second to the eleventh inclusive. In the last it is not 
perceptible : in the first it is not distinguishable from the tuberosity. 

The first two and the last two ribs present some peculiarities deserving of notice. 

The first rib is shorter and broader than either of the succeeding ones, its direction is nearly horizontal; its body not being 
twisted, as is the case in other ribs, it lies evenly when placed on a plain surface. One surface looks upwards, and is marked by 
two very slight depressions, (over which slide the subclavian vessels,) and an intervening roughness, sometimes well marked, 
which indicates (he attachment of the scalenus anticus muscle. The other surface looks downwards, towards the cavity of the 
thorax. The external border, convex and rounded, is surmounted by the tuberosity ; the internal is thin, and forms the margin 



52 

of the superior aperture of the thorax. The anterior extremity is broad and thick; the head, which articulates with the first 
iZ venebra, is small, presents an undivided articular surface, and is supported by a slender neck. 

PLATE XXIX. 

The ligaments of the ankle, and bones of the tarsus. 

Fio. 1. The os calcis of the right foot,— its upper surface. 

No 1. The posterior tuberosity. 2, 2. The two surfaces which articulate with the under part of the astragalus. 3. The groove for the 

' interosseous ligament. 4. The outer border. 5. The cuboid surface. 
Fig. 2. The under part of the astragalus of the right foot. 
Nos. 1, 1. The surfaces which articulate with the os calcis. 2. The groove for the interosseous ligament. 3. The groove for the tendon 

of 'the flexor longus pollicis muscle. 4. The rounded head of the astragalus. 
Fig. 3. The scaphoid bone of the right foot,— its anterior surface. 
No 1. The upper border. 2. The facet which articulates with the external cuneiform bone. 3. The facet for the middle cuneiform 

' bone. 4. The facet for the internal cuneiform bone. 5. The under surface. 6. The tuberosity. 7. The broad extremity. 
Fig. 4. The posterior surface of the scaphoid bone of the right foot. 
No. 1. The concave surface which articulates with the head of the astragalus. 2. The upper border. 3. The lower border. 4. The 

broad extremity. 5. The tuberosity. 
Fig. 5. The internal cuneiform bone of the right foot. 

A. The anterior border of this bone. 

No. 1. Its upper extremity. 2. Its lower extremity. 3. The outer suriace. 4. The inner or subcutaneous surface. 5. The facet 
which gives attachment to the tendon of the tibialis anticus muscle. 6. The metatarsal surface. 

B. The posterior border of the same bone. 

No. 1. The facet which articulates with the scaphoid bone. 2. The facet which articulates with the middle cuneiform bone. 3. A 
small facet for articulation with the base of the metatarsal bone of the second toe. 4. The apex of the bone. 5. Its base. 6. Its 
external surface. 7. Its internal or subcutaneous surface. 

Fig. 6. The middle cuneiform bone of the right foot. 

A. The internal surface of this bone. 

Nos. 1,1. The facet which articulates with the internal cuneiform bone. 2. The upper surface of the bone. 3. Its inferior border. 

4. Its anterior border. 5. Its posterior border. 

B. The same bone, viewed upon its external aspect. 

No. 1. The facet which articulates with the external cuneiform bone. 2. The rough surface for attachment to interosseous ligaments. 
3. The upper surface of the bone. 4. The inferior border. 5. The anterior border. C. The posterior border. 

C. The posterior border of the same bone. 

No. 1. The facet which articulates with the scaphoid bone. 2. The base of the bone. 3. Its inferior border. 4. The internal surface. 

5. Its external surface. 

Fio. 7. The external cuneiform bone of the right foot. 

A. The external surface of this bone. 

No. 1. The facet for articulation with the cuboid bone. 2. A rough surface for the attachment of the interosseous ligaments. 3, The 
superior border of the bone. 4. Its inferior border. 5. The anterior border of the bone. 6. Its posterior border. 

B. The internal surface of the same bone. 

No. 1 . The upper surface of the bone. 2. Its inferior border. 3. The anterior border. 4. The posterior border. 5, 5. The metatarsal 
surface. 6. The facet which articulates with the middle cuneiform bone. 

C. The anterior border of the same bone. 

No. 1. The facet which articulates with the base of the metatarsal bone of the third toe. 2. The dorsal surface of the bone. 3. The 
inferior border. 4, 4. The facet which articulates with the base of the metatarsal bone of the second toe. 5. The outer'surface of 
the bone. 

Fig. 8. The cuboid bone of the right foot. 

No. I. Its dorsal surface 2 Its plantar surface. 3. The peroneal groove. 4. A smooth facet for a bursa mucosa. 5. The outer 
horder of the bone. 6. I he anterior or metatarsal surface. 7. The posterior surface of the cuboid bone. 

r- Hi. J. 1 he ankle-joint, seen upon its anterior aspect : after Bourgery. 

No. 1. The tibia. 2. The fibula. 3. The interosseous lio-ament° 4 The antorinr v, mmont „f ,u ■ r ■ ,.,.,. 

5, 5. The anterior ligament of the ankle-joint. C. Th°e internal itienti i.am en ^ Th IT" ^^^ »«™^™- 

nonce formed by the astragalus. 9. The scaphoid bone 10 T^ ! cuboid b „e!' ^ hSament - * A ^ 

Fig. 10. The ankle-joint, viewed from behind : after Bouro-ery 

^^le^^^ 

muscle. 7. The posterior ligament. 8. The tra vis Uam n T /"""i ^ r^^ *"* ^ *"* ^^ 

ligament,-i,s middle fasciculus. 11, 11. I ts " ior ^ c cuT 12 Th 1 1,gament - ^ T " e ^^ M 

longus pollicis muscle. 13. The posterior tuberosity of tl,eosca, cis ^^ "P™ ^ ^'^ f ° r th ° tGnd ° n ° f the fleX ° r 

Fig. 11. The ankle-joint, viewed from the internal aspect: after Bounrerv 

N , 1. The tibia. 2. The fibula. 3,3. The internal lateral lament 1 Thn . ., -j , 

tibialis posticus muscle. 6. The .rroove for the tendon- ,f, , ! scaphoid bone. 5. A groove for the tendon of the 

os calcis. 8. The tendo fkchilli. " ,0ngUS ^"^ and flexor 1 ™S»* P ' 1 ^ "'^cles. 7, 7. The 



r/afr Z9 




53 

The second is longer than the first, and presents externally a prominent line for the attachment of the serratus magnus ; its 
internal surface is somewhat grooved posteriorly. 

The eleventh has no groove on its inferior border, nor a tubercle, as it is not articulated with the transverse process ; its angle 
is scarcely perceptible, and the head has but one articulating surface. 

The twelfth differs little from the preceding one, except in being shorter ; it has neither angle, tubercle, nor groove, and as 
its anterior extremity, which is pointed, seems loose and unattached, it is called the floating rib. 

The ribs grow from three osseous points ; one in the body, one in the head, the third being at the tuberosity. 

Costal cartilages. — These cartilages are twelve in number, like the ribs, of which they form the elastic continuation ; their 
breadth diminishes gradually from the first to the last, whilst the length increases as far as to the seventh, after which it becomes 
less in each succeeding one. Their line of direction also varies considerably. The second is horizontal, the first descends a little, 
and all the rest ascend more and more as they are situated lower down. The external or costal extremity, convex and unequal, 
is implanted into the end of the corresponding rib. The internal extremities of the cartilages of the true ribs, smaller than the 
external, and somewhat pointed, are articulated with corresponding angular surfaces on the sides of the sternum ; each of the 
cartilages of the first three false ribs, becoming slender towards its extremity, is attached to and blended with the lower border of 
that which is next above it ; in the two last it is pointed, and unattached. 

Attachment of muscles. — The two layers of intercostals, to the contiguous borders of all the ribs; the scaleni, to the first and 
second ; the pectoralis major, to the cartilages of the true ribs, except the first ; pectoralis minor, to the bodies of the third, fourth, 
and fifth; rectus abdominis, to the cartilages of the last three true ribs and ensiform cartilage; obliquus externus, to the last three 
true ribs and all the false ; the internal oblique and transversalis, to the cartilages of the four or five false ribs; the diaphragm, to 
the ensiform cartilage, and to those of the last six ribs. 

The serratus magnus, to the nine superior ribs; latissimus dorsi, to the four inferior; serratus posticus superior, to the third, 
fourth, and fifth true ribs ; serratus posticus inferior, to the three last ; sacro-lumbalis, to the angles of all the ribs ; levatores 
costarum, a little beyond the tuberosities. 

Bones of the superior extremity. — The upper extremity consists of the shoulder, the arm, the fore-arm, and the hand. The 
shoulder consists of the scapula and clavicle; the arm, of the humerus; the fore-arm, of the radius and ulna; and the hand, of the 
carpus, metacarpus, and fingers. 

Scapula. — This bone [plate XVI.] is placed upon the upper and back part of the thorax, occupies the space from the second 
to the seventh rib, and forms the posterior part of the shoulder. 

Its form is irregularly triangular and flat. It presents for examination two surfaces, three borders, and three angles. 

The anterior surface, called also fossa subscapulars, looks towards the ribs, is triangular, slightly concave, intersected by 
prominent lines directed from within outwards and upwards, and therefore crossing the direction of the ribs. 

The posterior surface (dorsum scapulae) is divided into two parts, but unequally, by a prominent ridge, (the spine :) of these, 
the superior one is called fossa supra-spinata ; the inferior, fossa infra-spinata. 

Of the spine. — The spine of the scapula is a prominent ridge of bone, flattened from above downwards, commencing at the 
posterior border of the scapula, with a smooth flat triangular surface, from which it becomes gradually more elevated as it pro- 
ceeds forwards, until it terminates in an elongated process, (acromion,) which surmounts the shoulder-joint. The form of the 
spine considered by itself apart from the acromion is triangular ; hence we have to notice its two surfaces and three borders. Its 
superior surface is concave, and, conjointly with the superior part of the dorsum of the scapula, forms the fossa supra-spinata. 
The inferior surface is irregularly triangular, constitutes part of the infra-spinous fossa, and in its middle may be observed a small 
foramen for a nutritious vessel. On the projecting border of the spine, which is rough and broad, may be noticed two margins, 
of which the superior one gives attachment to the trapezius, the inferior to the deltoid muscle, — the intervening edge is subcuta- 
neous. The anterior or attached border, or base, is united with the dorsum of the bone. The external border, which is short, 
round, and somewhat concave, approaches the neck of the bone, and is continuous with the under surface of the acromion. 

Of the acromion process. — This considerable eminence is flattened in the direction opposite to that of the spine, and, project- 
ing outwards and forwards, forms the summit of the shoulder-joint; hence its designation, axpo, a summit; <o,uo;, the shoulder.) 
Its posterior and upper surface, convex and somewhat rough, is subcutaneous; the anterior and inferior one, concave and smooth, 
is in relation with the supra-spinatus muscle, and overlies the capsular ligament of the shoulder-joint; the superior border pre- 

Fig. 12. The ankle-joint, viewed upon its external aspect : after Bourgery. 

No. 1. The tibia. 2. The fibula. 3. The anterior ligament. 4. The anterior fasciculus of the external lateral ligament. 5. Its middle 
fasciculus. 6. Its posterior fasciculus. 7. The scaphoid bone. 8, 8. The os calcis. 9. The tendo Achillis. 

Fig. 13. A vertical section of the ankle-joint, showing the cavity of the articulation and the interosseous ligament of the calcaneo- 
astragaloid articulation: after Bourgery. 

No. 1. The tibia. 2. The fibula. 3. The interosseous ligament. 1. The cavity of the ankle-joint. 5. The astragalus. 6,6. The 
os calcis. 7. The internal lateral ligament of the ankle. 8. The external lateral ligament. 9. Tin- calcaneo-astragaloid interos- 
seous ligament. 



54 

interiorly, a narrow oval surface for its articulation with the external extremity of the clavicle, and its summit affords 

hment to the coraco-acromion ligament. 

The fossa supra-spinata, wider towards its vertebral than the other extremity, is filled up by the supra-spinatus muscle. 
The fossa infra-spinata, much larger than the preceding, is convex in the middle, somewhat concave, or rather grooved, inferiorly. 
• -ii die latter part and the axillary border is a slightly raised and elongated ridge, which extends from the glenoid cavity 
obliquely downwards to within an inch of the posterior angle of the bone, where it subsides into a flat and nearly quadrilateral 
surface. This latter part it is that gives origin to the teres major muscle, and over it slides the latissimus dorsi. Along the upper 
and rounded part arise the fibres of the teres minor; whilst the line of division between them marks the attachment of an 
aponeurosis, common to these muscles and to the infra-spinatus, which occupies the remainder of the fossa. 

Of the tlirce borders of the scapula, or costae, (as they are sometimes called,) the superior is the shortest; at its outer part is 
situated a lunated notch, (lunula ; incisura semi-lunaris,) which is converted into a foramen by a ligament, and is traversed some- 
times by the supra-scapular vessels and nerve, but usually by the nerve alone. In front of this opening it is surmounted by the 
carnroid process, which, being thick, elongated, and curved on itself, is named from some fancied resemblance to a crow's beak, 
• a crow ; m«05, like.) This process, superiorly convex and unequal, gives attachment to the coraco-clavicular ligament- 
anteriorly to the pectoralis minor muscle; posteriorly to the coraco-acromion ligament; and by its extremity to the biceps and 
coraco-bracliialis muscles. The posterior, or vertebral border, named also the "base" of the scapula, is the longest of the three- 
superiorly it approaches to the vertebral column, inferiorly it is more removed from it. The portion of this border which is above 
tlir gpine will be observed to incline a little outwards. For the purpose of more easily assigning the attachments of the several 
muscles which are connected with it, we may regard it, though very thin, as divisible into two margins, with an inter-space- 
these ore state,] m tli<- enumeration of the muscular attachments. The axillary border is inclined downwards and backwards 
from the lower margin of the glenoid cavity to the inferior angle of the bone ; hence it is named the inferior costa of the scapula. 
It is of considerable thickness, being surmounted posteriorly by the ridge above noticed as giving origin to the teres minor. The 
edge itself presents a shallow groove running along the greater part of its extent. It corresponds with the lower border of the 
sub-scapulaj muscle. For about an inch beneath the glenoid fossa there is a well-marked linear impression, which gives origin 
to the long head of the triceps muscle. 

PLATE XXX. 

Tin' Ligaments of the foot. 

In:. 1. The superficial ligaments of the dorsum of the foot: after Bounrery. 

No.l The astragalus 2. The 03 calci s . 3. The tendo Achillis. 4,4. Calcaneo-astragaloid ligaments. 5,5. Dorsal ligaments of 
- he ,,«„, 0. The tendon of the penmen, longu, 7. The tendon of the tihiajposticj. 8. The internal enn 1 rm o. 
To externa cune.tonn hone. 10. The cuboid bone. 1,, 1,. Tarso-metatarsal ligaments. 12, 12. Metatarsal ligament. 
13 13 Lateral ligaments of the metatarsophalangeal articulation. 14, 14. A band of the deep fascia of the foot 15 A me 
.rs.-phah,,,,,,, articulation latd open. 10, ,6. The transverse ligaments. 17, 17. The later/ligaments of the P h lanlf alu- 
lano s. 18. 1 he tendon of the extensor propnus pollicis. 19. One tendon of the extensor communis dMtornm 
Fio. 2. Dee,, laments of the dorsum of the foot: after Bourgery. quorum. 

No. 1. The astragalus. 2, 2. The os calcis. 3, 3. Ligaments connecting these two bones a Th , a a un- 
bone. 6. The articulation between the astragalus and the scaphoid "bon 7 A ^ tendo Ach.lhs. 5. The scaphoid 
cuneiform hones. 11. The cuboid bone, g 12 . The a^lt^orm' tSS^t^ f ? J ? ^ ^ 
bones. 14. The cuboido-cuneiform articulation. 15. A calcaneocuboid li.ameT 6 If T. , * ^ 
17, 17. The lateral metatarsal articulations. 18, 18. The metatarsal bones tarso-metatarsal articulations. 
Fie. 3. The superficial ligaments of the sole of the foot : after Bounrery 
-V.. 1 . 2. The os calcis. 3. The groove for the tendon of the flexoHongus pollicis 4 4 Th„ I 

tendon of the tibialis posticus. 6, 7. Prominences caused by the scaphoid and ,h , , Ca,Can r e °- SCa P hold ^™"t. 5. The 
ealcaneo-o,,,,,,,,, Hgamen, 9, 9. The deep calcaneocuboid ligamen, 7 1 T IT TT*"" ^ 8 ' 8 " ^ *""" 
nor tarso-metatarsal ligaments. 12, 12. Metatarso-metatarsal laments ' 13 ! , T, °" Per ° neUS l0ngUS - "' "' Infe " 

plantar fascia. 15, 15. Ligamentous bands which serve to retabthTtP^ r u a m6tatarSal bones - 14, 14. A part of the 

ment of the metatarso-phalangeal articulation. 17 17 The inferin r "" °r muscles. 16, 1G. The transverse liga- 

rnetatarso-phalangeal articulations. 19. One of the metatarso ,hl T ! articulation - J 8> 18. Lateral ligaments of the 
-Dents. OL.l. Inferior pha.angeal ligaments. 2 oTo^e ^!T T T * ^ ^ 20 ' 2 ^ Lateral phalangeal liga- 
I'.... 4. The deep ligaments of the sole of the foot : after Bour.er ° "t.culations laid open. 5 

Won. 1, 1. The os calcis. 2. The groove for the tendon of iC fl , 

4- The deep calcaneocuboid ligament. 5,5. Cuhoido-cte LTm Smen^^V V' ^ "^ ^™™*^ »*«"«.. 
r or tarso-metatarsal hgament of the great toe. 8. The tendon of thin! ,' ' Metatars °- me ^arsal ligaments. 7. The infe- 

•. vertical section of the foot, showing the interosseous vZll- °T ^ m " SCle - "' °' Mctatarsal -ones. 
1. The tibia. 2. The astral as 3 3 The i " r nts> after Bourgery. 

posterior ligament. C. The°os calcis.' 7. The uZ LuL'^jt' V? ™*™ H S ament °f^ articulation. 5. The 

,S: T,^, 1 V ar !. 0f,heCalCane " SCa P h0idli ? am -t. 11 The'iltT' /° ne - 9 - The -lcaneo-astragaloid interosseous 

toe. 13, 1 . t he phalanges of the great toe. 14. One of the s s m h CU " ( ' lf ° rm ^ ! " """ metetaraa] "«■ of the great 

calcaneocuboid ligament. s ^ a ™d bones. 15. Metatarsal bones. 16. The great or superficial 



Hones 



/'/,r/f 30 



/<'/</ / 





Fuf. J 



Fig 2 





/■'/// 5. 




//', .y,',/: , by A Neivsam 



Vliflitdflphia rnittitthcd /"■ ('nrer t ffart. 



r.3 Duval tvth.FhU? 



55 

The postero-superior angle is formed by the junction of the base with the superior costa of the scapula ; it is somewhat 
inclined outwards. The inferior angle is placed at the union of the base with the axillary or inferior border of the bone; upon 
it may be observed an elongated flat surface which gives origin to the teres major, and over which slides the latissimus dorsi mus- 
cle. At the convergence of the superior and inferior borders may be observed a narrow constricted part, denominated the neck, 
(cervix scapulas.) The neck is bounded by a slightly-raised rim, which gives attachment to the fibrous capsule of the shoulder- 
joint ; and finally the rim surrounds the articular surface of the bone, which is called the glenoid cavity, (y^vr,, a superficial 
cavity ; «8o{.) This is a shallow, oval depression, broader below than above, covered with cartilage in the fresh state, and deep- 
ened somewhat by a fibro-cartilaginous margin, which passes round it from the long tendon of the biceps muscle, whose origin is 
at its upper margin ; its greatest diameter is perpendicular, its direction outwards and forwards. In this last respect, however, it 
varies considerably ; for, during the more extended motions of the humerus, the scapula is made to turn, as it were, on a pivot 
driven through the centre of its dorsum, by which means the glenoid cavity is kept constantly in apposition with the head of the 
humerus, which is the chief security against its dislocation. 

The scapula articulates by its glenoid cavity with the humerus, and by the acromion process with the clavicle ; it affords 
attachment to the following muscles : — 

The subscapular fossa, (the anterior or costal surface of the bone,) to the subscapularis muscle. Posterior or dorsal sur- 
face, — the spine (by its border and the acromion) superiorly to the trapezius, inferiorly to the deltoid: the fossa supra-spinata, by 
its posterior two-thirds, to the muscle of the same name : the fossa infra-spinata, in the greater part of its extent, to the infra-spi- 
natus ; by a slight oblique line situated near the inferior angle, to the aponeurosis common to the infra-spinatus, teres minor, 
and teres major ; by a narrow rounded surface, near the axillary border, to the teres minor ; by the flat surface, at its inferior 
angle, to the teres major. 

The superior border, near the margin of its notch, to the omo-hyoideus : the coracoid process, anteriorly, to the pectoralis 
minor ; by its summit, to the biceps and coraco-brachialis. The posterior border or base, anteriorly, to the serratus magnus ; 
posteriorly, to the supra-spinatus and infra-spinatus ; in the interspace, to the rhomboidei and to the levator anguli scapulae. The 
inferior or axillary border, at its upper part, by a rough ridge, to the long portion of the triceps extensor ; posteriorly, by an un- 
equal surface, to some fibres of the teres minor ; inferiorly, to the teres major. 

The inferior angle, to the teres major, and occasionally to some fibres of the latissimus dorsi; the anterior angle, (glenoid 
cavity,) by its upper margin, to the long head of the biceps muscle. 

Developement. — When the scapula is examined at a very early period, it appears as a thin lamella without any elevation 
corresponding with the spine. Soon after, an osseous centre is seen towards the middle of its dorsum, one in the coracoid process, 
and in the acromion. The base and the inferior angle also commence by separate points. 

The Clavicle. — The clavicle, (clavis, a key,) (plate XVI. figs. 1, 2 ; plate XVII. figs. 4, 5;) or, as it is popularly called, the 
collar-bone, is extended, transversely, between the acromion process of the scapula and the summit of the sternum, which it serves 
to connect; its direction, however, is not exactly horizontal, the acromial end being slightly elevated. This bone is curved some- 
what like an italic /, the degree of the curvature being less in young and female subjects than in male adults; it is rather thick 
and somewhat triangular towards its sternal end, but broad and flat towards the scapular extremity; it presents for our consider- 
ation a body and two extremities. The superior surface of the body is principally subcutaneous. The inferior surface presents, 
near the sternal extremity, inequalities for the attachment of the costo-clavicular ligament ; in the centre, a longitudinal depression, 
giving attachment to the subclavius muscle, the foramen for the entrance of the medullary vessels, and, more externally, a rough 
oblique line, to which the coraco-clavicular ligaments are attached ; this surface corresponds internally to the first rib, externally 
to the coracoid process and the shoulder-joint, and in the middle to the axillary vessels and brachial plexus of nerves. The ante- 
rior border is broad and convex towards the sternal, thin and concave towards the scapular extremity ; the posterior border 
presents, of course, the opposite arrangement of curvatures. The internal extremity is inclined downwards and forwards; it is 
considerably thicker than the other parts of the bone, and terminates in a triangular unequal surface, which is convex from above 
downwards, concave from behind forwards: this is tipped with cartilage, and articulates with the sternum, the articular surface 
of which it much exceeds in size; its entire circumference gives attachment to ligaments. The external or scapular extremity, 
compressed and flattened, inclines a little backwards and upwards, and articulates with the acromion by a narrow oblong surface 
which is covered with cartilage. 

. lltachmcnts of muscles. — The clavicle gives attachment, by the superior surface of its sternal extremity, to the sterno-cleido- 
mastoid ; the longitudinal depression on its inferior surface, to the subclavius; the anterior border, by its sternal half, to the pecto- 
ralis major; by its acromial third, to the deltoid; the posterior border, by its acromial third, to the trapezius. 

Articulations. — The clavicle articulates with the sternum and the acromion process of the scapula. 

Developement. — The division of the bone above indicated into body and extremities is merely technical, being intended to 
facilitate its description. It consists of one piece, and grows from one ossific centre. 

The Humerus. — The humerus or arm-bone, (plate XVII. figs. 1, 2, 3 ; plate XVIII., os humeri,) the largest bone of the 
upper extremity, extends from the scapula to the bones of the fore-arm, with each of which it is articulated. Its direction is ver- 



56 
,„,, with an inclination inwards .owards the lower end. Long and irregularly cylindrical in form, the humerus is divisible into 

r^Z: "me bone, duck and rounded superiorly, rs somewhat expanded, and triangular infer.orly ft is divided 
,„,„ ,1 ^ r v c<mal surfaces by two longitudinal lines, of which one is external and antenor the other mteraal and posterior. 
imoiwoiRdii) uiua j o ovtprna i the latter from the internal condyle, near to which they are 

Tin. s«- lines miv be cons dered as rising, the former from the external, me iduei «uui / > j 

.STSi^SdJ subside as they proceed npwards on the body of the bone ; they afford attachment to the inter-mus 
c-„i:ir aponeuroses The external one is interrupted about the middle by an oblique depression or groove, which runs from above 
downwards, and marks the course of the musculo-spiral nerve and superior profunda artery ; the surfaces separated by these lines 
are named posterior and anterior. The posterior surface is round superiorly, and inclined a little inwards ; in the lower par it is 
broad dat, and turned rather outwards; it is covered in the entire of its extent by the triceps extensor muscle, and towards its 
middle may be observed a small foramen for the medullary vessels. The anterior surface is divided superiorly into two unequal 
portions ky a longitudinal groove, directed obliquely downwards and inwards, for about one-fourth of the length of the bone; 
this Lodges the long tendon of the biceps muscle, and is therefore named the bicipital groove ; its anterior margin gives attachment 
to the pectoralis major ; the posterior, to the latissimus dorsi and teres major. The portion of the anterior surface which is internal 
to .Lis groove is smooth in the greater part of its extent, and presents, towards its middle, a linear elevation for the insertion of 
the roraco-brachialis, and lower down an oblique medullary foramen ; externally to the groove, and a little above the middle 
of the bone, may be observed a broad rough eminence, for the insertion of the deltoid muscle, beneath which runs the oblique 
depression already noticed as corresponding to the course of the musculo-spiral nerve and the accompanying artery. 

The superior extremity of the bone presents a large hemispherical eminence, covered with cartilage in the fresh state, and 
directed backwards and inwards to the glenoid cavity of the scapula, with which it articulates; this is called the head of the 
humerus. It is bounded by a slightly depressed groove, sufficiently marked on the upper, not on the under aspect, denominated 
the neck of the bone. A little beneath, and to the outside of the head, are two eminences, which project from the ends of the 
shaft of the bone, and from their relative size, are named the greater and lesser tuberosities, (tubercula.) The greater tuberosity 
is external and posterior in its situation, convex in its outline,, and marked on its upper border by three flat surfaces for the inser- 
tion of tlic external rotator muscles. The smaller tuberosity, rounded and more prominent than the other, gives attachment to the 
ipularis muscle. They are separated by the bicipital groove. Towards its lower third the bone widens, and appears com- 
pressed and somewhat twisted from behind forward ; its greatest diameter is transverse; it presents internally a considerable 
projection, the inner condyle, which is inclined backwards, and gives attachment to the internal lateral ligament of the elbow- 
joint, and to a tendon common to the greater number of the anterior muscles of the foramen. Externally is situated another 
smaller process, (externa! condyle,) to which are attached the external lateral ligament and a tendon common to the muscles of 
the posterior and external surfaces of the fore-arm. Between the condyles is placed the inferior articular surface, which is inclined 
somewhat forwards. Proceeding in the enumeration of the parts which enter into its composition from the radial to the ulnar side, 
we observe a rounded eminence placed rather on the anterior surface of the bone, and articulating with a cavity observable on the 
superior extremity of the radius, calculated to allow of all that freedom of motion which the radius enjoys, viz., flexion and ex- 
tension on the humerus, and pronation and supination by rotation on its own axis; — a slight groove or depression corresponding 
with the circumference of this eminence, a semicircular ridge, which is lodged in the space intervening between the radius and 
ulna ;— a wide and deep groove, which receives the prominent part of the larger sigmoid cavity of the ulna ; and, lastly, a promi- 
nent ridge, which is received into the internal part of the same cavity. This prominence descends much lower than the external 
portion of the articular surface, and determines an obliquity in the direction of the humerus, when its lower extremity is made to 
res, on a plain surface. The groove, with its margins, forms a well-marked pulley-like surface, on which the sigmoid cavity of 
the ulna moves in flexion and extension ; hence it is termed the trochlea. At the fore part of the inferior extremity of the bone, 
and immediately above the trochlea, is a superficial depression, which receives the coronoid process of the ulna during flexion; 
and posteriorly a more considerable fossa, which lodges the olecranon during the extension of the fore-arm 

A modification of the nomenclature applied to these different eminences has been proposed by Chaussier ; retaining the term 
trochlea for the surface of articulation with the ulna, he calls that which articulates with the radius, the condyle ; (it is sometimes 
called the small bead;) and for the two lateral eminences of insertion, now named condyles, he substitutes the terms epi-lrochlea 
and cpi-conayle. r 

Attachments oj 'muscles. .-The posterior surface gives attachment to the triceps ; the anterior, (by the posterior margin of the 

iX n tThrd ° T 7 maJ °r lat - imus . dorsi -> - the middle, by a slightly-marked line, to the coraco-brachiahs ; mfe- 

no to the brae h. lis amicus ; -the external portion of the same surface, superiorly, by a rough eminence, to the deltoid ; by the 

r ™unSrd°er to tnTlHT' ? ZT* "*"' ^ »"" taberod * ^ attachment, by the three flat surLes 
^Zo ^ «* *- '« to the subscapular, 

longior and brevio, extensor communis ^^^^S^l " ^ ^^ * *" ^^ "* "** 

aiiurum, extensor carpi ulnans, anconeus and supinator radii brevis ; by the internal 



57 

condyle, to a tendon common to the pronator radii teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris, and flexor 
digitorum sublimis. 

Articulations. — The humerus articulates with the glenoid cavity of the scapula, and with the ulna and radius. 

Developement. — The shaft of the bone grows from one ossific centre ; the head and two tuberosities have each their own 
points. So have the two condyles and the trochlea. 

The Radius. — The radius, (plate XVII. figs. 1,2, 3 ; plate XIX. fig. 1,) shorter than the ulna by the length of the olecranon 
process, is placed at the external side of the fore-arm, extending from the humerus to the carpus. It is broader below than 
above, slightly curved in its form, and divided into a body and two extremities. As the body is somewhat triangular, we observe 
on it three surfaces, bounded by three margins or ridges. The anterior surface expands towards the lower part, and is marked 
along its middle by a longitudinal groove for the flexor pollicis longus ; superiorly is situated the foramen for the medullary 
vessels, its direction being from below upwards ; and inferiorly a flat surface, corresponding with the pronator quadratus. The 
posterior surface, convex in the greater part of its extent, is grooved at its central third, for the origin of the extensors of the 
thumb ; the external surface, round and convex, is marked towards its middle by a rough impression, which gives insertion to 
the pronator radii teres. Of the margins separating these surfaces, the posterior is distinct only at the middle part ; the external 
is round, and becomes smooth towards the lower extremity ; whilst the internal is acute and sharp, for the attachment of the in- 
terosseous ligament. The body is terminated superiorly by a rough prominence, (tuber radii.) termed the bicipital tuberosity, 
from its giving insertion to the biceps muscle. 

Above the tuberosity the bone becomes narrowed and constricted into the form of a neck, which is again surmounted by the 
head, intended by its extremity to articulate with the round convex part of the lower extremity of the humerus, its small head, 
(condyle, Chauss.,) while its margin rolls on the lesser sigmoid cavity of the ulna. The margin is smooth and convex ; the upper 
surface, also smooth, is a shallow cup-like cavity ; and both are covered with cartilage in the recent state. 

The radius at its lower part becomes broad and thick; the anterior surface is flat and expanded, being covered by the 
pronator quadratus muscle ; it is bounded below by a prominent line, which gives attachment to the anterior ligament of the 
wrist-joint. The posterior surface is convex, and marked by grooves which transmit the tendons of 'the extensor muscles; of 
these, one, which is very narrow and oblique in its direction, and nearly in the middle line, lodges the tendon of the extensor 
pollicis, (secundi internodii.) At the inner or ulnar side of. this is placed another, much broader, which transmits the tendons of 
the extensor communis and indicator; and at its outer side, a third, divided into two parts by a linear impression, marks the 
passage of the flexor carpi radialis, longior and brevior. Corresponding with the external border of the bone is another groove, 
directed obliquely forwards, and divided into two parts, for the tendons of the extensores — primi internodii, and ossis metacarpi 
pollicis. The outer side of the bone, particularly the part corresponding with the ridge which separates the two latter grooves, 
is prolonged downwards, and named the styloid process ; it affords attachment to the external lateral ligament of the wrist-joint. 
On the inner side of the bone is situated a small cavity, (semilunar,) covered by cartilage, which articulates with the inferior 
extremity of the ulna. At its inferior extremity the radius presents its carpal articulating surface, (scaphoid; navicular,) which 
is included between the base of the styloid process and the oval cavity just mentioned, bounded before and behind by two rough 
margins for the attachment of the radio-carpal ligaments. It is divided from before backwards, by a line, into two unequal por- 
tions, of which the external is triangular, and articulates with the scaphoid bone ; the internal is square, and articulates with the 
semilunar. 

Attachments of muscles. — The anterior surface of the body, by its grooved part, to the flexor longus pollicis ; by the 
oblique line, leading from the tuberosity to the insertion of the pronator ; radii teres, to the supinator brevis and flexor sublimis • 
its inferior fifth, to the pronator quadratus ; the posterior surface, by a slight concavity in the middle, to the extensores pollicis • 
the external margin, by a rough surface, to the pronator teres ; inferiorly, to the pronator quadratus and the supinator radii 
longus ; whilst the posterior part of the bicipital tuberosity gives attachment to the biceps muscle. 

Articulations. — The radius articulates with the humerus, the ulna, the scaphoid and semilunar bones. 

Developement. — It has a centre of ossification for its body, and one for each extremity. 

The Ulna.— The ulna (plate XVII. figs. 1, 2, 3; plate XIX., <ox £l ^, cubitus) is placed at the inner side of the fore-arm; it 
is a long and rather irregular bone, larger at the upper than at the lower extremity, — a conformation the reverse of that which 
obtains in the radius. Its body, or shaft, is marked off into three surfaces by three prominent lines. These are all broader above 
than below, in consequence of the decreasing size of the bone. The anterior surface, slightly depressed, is grooved longitudinally 
for the origin of the flexor profundus, and marked at its upper third by a foramen, directed obliquely upwards for the medullary 
vessels. The internal surface, smooth and somewhat excavated superiorly, is covered in the greater part of its extent by the 
flexor profundus muscle; it becomes round inferiorly, where it is subcutaneous. The external surface, rough and irregular, is 
divided into two parts, of which one, of small extent, corresponds with the superior extremity of the bone, and forms an elongated 
depression for the anconeus muscle ; the other, reaching to the lower extremity, gives origin to the extensors of the thumb and 
the supinator radii brevis. Of the three margins, the internal and posterior are round, and for the most part smooth ; the external 
is sharp, and gives attachment to the interosseous ligament. 
Boxes. — S 



58 
At tllc superior extremity of the bone a, situated two eminence, so ^ as ^^^^^* rf -^ 

- * ' — « theSC ' °7' Calle ^:^- f ;i ' ^^ cls^t llrio 5 : surface. The olecranon terminates 

- r ' ,h(> ^' 'r^^ -tensor; the latter being lodged, when the 

in a tough tuberosity and an obtuse pom t, * e ^ r f l ^ Antenorly , this process is smooth and hollowed out, to form 

^T^rfEEE^^ ^angular surface, which is subcutaneous. 

pari of the surface of articulation with the : ■ , P * anterior surface of the bone, and terminates in a 

2ES *JE^E SKS^I^ during the flexion into the anterior depression in the humerus; 
slurp ,1,L, ' w 7 h0 ^"* a ° nd trian „ u i ar ,ives insertion to the brachialis anticus muscle; its upper aspect is smooth and era 

i u 2 utv which articulates with the head of the radius. The great sigmoid cavity, formed by the junction of the 

:;;;:: :::;:: ^ t:^,^^ .named ^ m ^^ ^1^ >»*»***« ^**<« 

Z hke ) as it was originally written. Covered by cartilage in its entire extent, it is divided into two parts (but unequally, 
£^J«£W^™^** running downwards from the peak or point of the olecranon to that of the 
coronoid process. This ridge and the concavities beside it correspond, the one with the groove, the others with the lateral parts 
of the trochlea. At the margins of the sigmoid cavity may be observed two notches, which mark off the parts of the surface 
which belong to the olecranon and the coronoid process respectively. -.'... 

At the inferior extremity of the bone, which is small and rounded, are situated two eminences, of which the external one, 
named the head of the ulna, round and covered with cartilage, presents two aspects, of which one, nearly circular in its form, 
looks towards the wrist-joint, and corresponds with the triangular fibro-cartilage of that articulation ; whilst the external one, 
narrow and convex, is received into the semilunar cavity in the contiguous border of the radius. The internal eminence, named 
the styloid process, projects on a line with the posterior and inner surface of the bone ; it is elongated in its form, and gives 
attachment to the internal lateral ligament of the joint. The head and the styloid process are separated posteriorly by a groove, 
winch is traversed by the tendon of the extensor carpi ulnaris, and inferiorly by a depression at the base of the styloid process 
into which the triangular fibro-cartilage is inserted. 

. Attachments of muscles. — The anterior surface, superiorly and m the middle, gives attachment to the flexor digitorum pro- 
fundus- inferiorly, to the pronator quadratus ; the posterior surface, to the anconeus, the extensor carpi ulnaris, supinator radii 
brevis, the ejrtensores pollicis, and the extensor indicis; by the posterior longitudinal line, to an aponeurosis common to the flexor 
carpi ulnaris, flexor digitorum profundus, and extensor carpi ulnaris. The superior extremity, by the summit of the olecranon, 
to the triceps brachialis ; the coronoid process, by its anterior rough surface, to the brachialis anticus ; and by its internal side, to 
the second origin of the pronator teres. 

Articulations. — The ulna articulates with the humerus and the radius; it has no point of contact with the carpal bones, but 
it is brought into relation with the cuneiform bone by means of the inter-articular fibro-cartilage. 

Developement. — The shaft of the ulna, as in other long bones, has its own osseous centre; so has the lower extremity or 
bead, as well as the olecranon process. 

Hand. — The hand (plate XX.) is composed of the carpus, metacarpus, and fingers. 

Carpus. — The first or superior part of the hand is named the carpus or wrist ; it is placed between the fore-arm and the 
metacarpus, and composed of eight small bones, which are disposed in two ranges, each consisting of an equal number. Pro- 
ceeding in the enumeration from the radial to the ulnar side, the bones which constitute the first or superior ran°-e are thus named 
from their shape— scaphoid, semilunar, cuneiform, and pisiform ; those of the second or inferior range are the trapezium, trape- 
zoid, os magnum, and unciform. The dorsal surface of the carpus is convex, the palmar concave and irregular, and marked by 
four bony prominences, across which is stretched the anterior annular ligament, so as to form a canal for the transmission of the 
tlexor tendons. 

Bones of the first row.— The Scaphoid bone.— The scaphoid or boat-shaped bone (plate XX.) (ox*n, a boat) is the first of 
tins row. and the largest. Its position is oblique, so that its broad end is directed towards the trapezium and root of the thumb, 
whilst the narrow one inclines inwards and upwards to the middle of the articular surface of the radius. It is convex on one side, 
concave on the other. The concave or hollowed surface (scaphoid) looks obliquely inwards and forwards, and is that which 
determines the form and gives name to the bone. Its upper articular surface, convex and triangular, is applied to the radius ; the 
lower, also convex articulates with the trapezium and the trapezoid bone. Its concavity receives part of the head of the os 
magnum; close to this is a narrow articular surface which is in contact with the semilunar bone; on its radial side is a rough 
S u r cbn ?n " T A "I ^v! ligament 0f the ™-Joint; posteriorly is a narrow grooved surface for the 

e r n = r ; r a t j ? a r s r face ' the inner ° r uinar haif ° f »** - ■— ^Lm Y grooved, vm* 

.he outer ,s prominent and tuberculated for the attachment of ligaments. It articulates with five bones. 

surfac?* iZ „h7 JT". T? b ° ne (Pkte XX ° iS takm from its bein § co '— °' -escentic on its inferior 

surface. Irregularh triangular m its form, convex superiorly, it articulates with the square part of the articular surface of the 



o9 

radius ; inferiorly concave, with the os magnum and the unciform ; on the ulnar side, with the cuneiform ; on the radial side, with 
the scaphoid ; anteriorly and posteriorly it gives attachments to ligaments. It articulates with five bones. 

The Cuneiform bone.— This is the " wedge-shaped" bone, (plate XX.;) sometimes also it is named from its form "pyramidal:" 
superiorly it is in relation with the inter-articular fibro-cartilage of the wrist-joint; inferiorly it articulates with the unciform bone; 
on the ulnar side, gives attachment to ligaments ; on the radial side, articulates with the semilunar bone ; anteriorly it affords 
attachment to ligaments, and presents a small articular surface for the pisiform bone. It articulates with three bones. 

The Pisiform bone.— The "pea-shaped" bone (plate XX.) is placed on a plane, anterior to the other bones of the carpus. 
Its form is indicated by its name, {pisum, a pea.) It presents but one articular surface, which is situated on the posterior part, or 
base, and rests on the anterior surface of the cuneiform bone ; it affords attachment to the annular ligament of the carpus, to the 
flexor carpi ulnaris muscle, and to the abductor of the little finger. 

The first three carpal bones form, when in apposition, a rounded convex surface, which corresponds with the concavity 
presented by the radius and the inter-articular cartilage; but their lower surface constitutes a deep hollow, which receives the 
head of the os magnum and the unciform bone. 

Bones of the second row.— The Trapezium.— The name of this bone (plate XX.) is taken from its presenting four unequal 
edges at its posterior aspect. It is placed at the radial border of the carpus, between the metacarpal bone of the thumb and the 
scaphoid bone. It is known by the angular appearance of its dorsal surface, and by the tubercle and groove at its palmar aspect. 
Superiorly concave, it articulates with the scaphoid bone ; inferiorly concave from "behind forward, and convex transversely, with 
the first metacarpal bone ; on the ulnar side, with the trapezoid bone, and, by a small surface situated more inferiorly, with the 
edge of the second metacarpal bone ; on the radial and posterior sides it gives attachment to ligaments ; anteriorly it presents a 
groove traversed by the tendon of the flexor carpi radialis, and a tubercle to which the annular ligament of the carpus is 
attached. It articulates with four bones. 

The Trapezoid bone.— This is a small bone, (plate XX.,) compared with those between which it is placed, viz. the trapezium, 
scaphoid, and os magnum ; in form and position it has some resemblance to a wedge, and but little to a trapezium, except that its 
posterior surface is bounded by four equal edges. It articulates superiorly with the scaphoid bone ; inferiorly, with the second 
metacarpal bone ; on the ulnar side, with the os magnum ; on the radial side, with the trapezium : the anterior and posterior 
surfaces afford attachment to ligaments. It articulates with four bones. 

Os magnum. — This (plate XV.) is the largest of the carpal bones ; its form is oblong, round superiorly, cubic inferiorly; the 
superior surface, named its "head," (whence it is sometimes called os capitatum,) is supported by a narrowed portion, named the 
" neck ;" its greatest convexity is in the antero-posterior direction, where it is received into a cavity formed by the scaphoid and 
the semilunar bone ; it articulates, inferiorly, by three distinct surfaces, of which the middle is the largest, with the second, third, 
and fourth metacarpal bones; on the ulnar side, with the unciform bone; on the radial side, with the trapezoid bone: the 
anterior and posterior aspects are rough (particularly the former) for the attachment of ligaments. It articulates with seven 
bones. 

The Unciform bone. — The " hooked-shaped" bone (plate XX.) {uncus, a hook) is readily distinguished from the rest by the 
curved process upon its palmar surface : it articulates, superiorly, with the semilunar bone ; inferiorly, by two distinct surfaces, 
with the fourth and fifth metacarpal bones; on the ulnar side, with the cuneiform bone; on the radial side, with the os magnum: 
anteriorly its hooked process affords attachment to the anterior annular ligament of the carpus; posteriorly a rough surface also 
gives attachment to ligaments. It articulates with five bones. 

The Metacarpus. — This (plate XX.) forms the second or middle portion of the hand, being situated between the carpus and 
the phalanges ; it is composed of five bones, which are named first, second, &c, in their numerical order, the enumeration "being 
commenced at the radial side. These bones are placed parallel one with the other, and nearly on the same plane, with the exception 
of the first, which is more anterior than the rest, and alters its relative position to them in its various movements. They vary in 
size, the first being thicker and shorter than the others ; and these gradually diminish in length from the second to the fifth. 
They are all slightly concave on the palmar surface, convex on the dorsal, larger at their extremities than in the bodies or middle 
part, terminated at the carpal extremity by an unequal eminence, and at the digital by a rounded head. 

The bodies are lengthened and somewhat compressed, but may, in each, be regarded as presenting a palmar, a dorsal, and 
two lateral surfaces. The palmar surface is narrow, and presents in the middle a prominent line, which separates the attachments 
of the interosseous muscles, and corresponds with the tendons of the flexor muscles ; as also, in the first, to the opponens and 
flexor brevis pollicis, and in the third to the origin of the adductor pollicis. 

The dorsal surface, convex and smooth in the first, presents in the second, third, and fourth a longitudinal line, which, 
bifurcating, forms the sides of a triangular surface, extending over two-thirds of their length ; in the fifth, also, is observed c 
prominent longitudinal line, directed obliquely from the ulnar to the radial side. The lateral surfaces afford attachment to the 
dorsal interosseous muscles; broad in the four last bones, these surfaces are narrowed, and form merely borders in the first. 

The carpal extremity presents, in each, some peculiarities which render a separate description necessary : on the first is 
observed a surface, which is concave in the antero-posterior and convex in the opposite direction, which articulates with the 



60 



f „„ ortW*.^ with the trapezoid bone, and on the radial side, a small surface, with the 
tt»periwiHn the second, a concave surface «t»*t« ™ th ^ P ^ rdg so ^ t0 bec0 me wedged in between the trapezium 
lrj ,,,„„„; at the ulnar ride, Us margin . extende ? ^^ ^^^ n the third , a nearly plain surface articu.ates 
and me thud metacarpal bone, and articulates by its tip with the os , magm , con - me tacarpal bones; on the 

Wllh tl , os magnum; on the radial and ulnar sides are "^^^^^Ttheie a & re two surfaces, and on the ulnar 
f(lll rth two articular surfaces move upon the os magnun .and T^™^,^^ the fifth, a concave surface, directed 

^^^^^ 

^^ :-" :£=■ ; he ba Se ^ *. *. *. r . :r 

d ome o he anatomists reckon three phalanges in the thumb, as they conceive that its posterior or most movable bone 
r ,„, me first phalanges of the fingers, rather than the metacarpal bones. But if its conformation be examined with attention, 
moTeTeeMy that of its anterior extremity, and also its mode of articulation with the bone in front of it ^analogy with the 
metecarpaTralge will appear more striking than with the first digital phalanges; and so it is considered by Meckel Portal H. 
I;., g^J The bodies of the first row or phalanx are convex on the dorsal surface, and flat from side to side on the 
palmar, but arched from before backwards ; the palmar surface is bounded by two margins which give insertion to the fibrous 
sheatte of the tlexor tendons. The larger or posterior extremities present an oval smooth surface, whose greatest diameter is 
from side to side, intended to receive the convex heads of the corresponding metacarpal bones. The anterior extremities, smaller 
than the other, end in two small lateral condyles, with a slight groove between them, both being adapted to the base of the con- 
tiguous bones, so as to form ginglymoid or hinge-joints. The articular surface is prolonged farther on the palmar than on the 
dorsal aspect, which allows a more free range to the motion of flexion. The margins of the articular surfaces are rough and 
prominent for the attachment of ligaments. 

The second row consists of four bones, the thumb having only two pieces corresponding with those of the first and last pha- 
lanx. Smaller than the preceding set, they still resemble them in their general outline. The broader or posterior extremity ends 
in an articular surface, divided by a slight ridge extending from before backwards, the lateral parts being concave for the recep- 
tion of the two eminences on the contiguous bone ; the anterior extremity is divided into two lateral convex surfaces, which are 
lodged in depressions in the base of the last phalanx. 

The third row (phalanges unguium, Soemm.) consists of five pieces, that of the thumb being the largest. They are convex 
on the dorsal, flat on the palmar surface ; rough at the summit, which corresponds with the points of the fingers, and at the base, 
for the attachment of ligaments and the flexor tendons. The articular surface, at the base, resembles that of the base of the 
second phalanx in having two shallow concavities divided by a central convex line. 

Attachments of muscles. — 1. To the carpal bones. The pisiform bone gives origin to the abductor minimi digiti, and in- 
sertion to the flexor carpi ulnaris ; the trapezium, to the opponens and abductor pollicis ; the trapezoid, to part of the flexor 
brevis pollicis; the os magnum, to part of the same; the unciform, to the flexor brevis (minimi digiti) and to the adductor. 

2. To the metacarpal bones. The frst, or that of the thumb, gives insertion to the extensor ossis metacarpi pollicis and to 
the opponens pollicis, and origin to part of the abductor indicis : the second, or that of the forefinger, to the flexor carpi radialis 
at its palmar end, and to the extensor carpi radialis longior on the dorsal surface of its base, and, by its lateral surfaces, to the two 
first dorsal interossei muscles and one palmar : the third, to the extensor carpi radialis brevior, to the adductor pollicis, and also 
to two dorsal interossei : the fourth, to two dorsal interossei and one palmar: the fifth, to the extensor carpi ulnaris, and the 
adductor or opponens minimi digiti, to one dorsal and one palmar interosseous muscle. 

3. To the bones of the fingers. Those of the first range of the four fingers give attachment by their lateral borders to the 
tendinous sheaths of the dexor tendons; their dorsal surface is covered by the expansion of the extensor tendons. The bones 
of the second row give insertion at their dorsal surface to the tendons of the extensor communis; the tendons of the flexor sub- 
limis are inserted. into their bases at the palmar surface. The third set gives insertion to the tendons of the flexor profundus; 
the fibres of the extensor communis are also continued on their dorsal aspect. 

The first phalanx of the thumb gives insertion to the extensor primi intcmodii, to the flexor brevis, to the adductor and 
abductor pollicis: the second phalanx to the flexor longns, and to the extensor secundi internodii. 

Qf the Pelvis.— The pelvis, or "basin-shaped" cavity (plate XV.) is placed at the lower extremity of the trunk, being 
formed by the union ot the ossa innominata, the sacrum, and the coccyx. Its form is somewhat circular ; its size presents many 
var.et.es, dependent on .he sex and age of the subject, as well as on individual conformation. In young subjects the two large 
lateral bones, .he ossa mnominata, arc divided each into three pieces, the ilium, ischium, and os pubis ; the sacrum consists of five 



61 

pieces, resembling in some respects the bones of the vertebral column, and hence called false vertebrae : these in adult age become 
united into one. The coccyx, or caudal prolongation, consists of four pieces. 

The Sacrum.— The sacrum, (plates IV. VI. XIV. XV.,) when the body is in the erect position, is placed at the superior and 
posterior part of the pelvis, beneath the last lumbar vertebra, above the coccyx, and between the ossa innominate, between which 
it is inserted in some measure like a keystone into an arch. 

Its figure is triangular in its general outline ; concave anteriorly, convex posteriorly. We consider successively its surfaces 
borders, and extremities. 

The anterior or pelvic surface is nearly flat from side to side, concave from above downwards, and marked by four transverse 
lines, indicating its original division*into five pieces; laterally it presents four foramina, (anterior sacral,) for the transmission of 
the anterior branches of the sacral nerves. These are directed outwards, and diminish gradually in size from above downwards ; 
external to these the surface gives attachment to the pyramidalis muscle. 

The posterior or spinal surface is convex and presents along the median line four small eminences, usually connected so as 
to form a ridge ; these are rudiments of the spinous processes ; and beneath them is a triangular groove, or rather an opening, 
marking the termination of the sacral canal. The margins of the opening present two tubercles, which give attachment to the 
ligament that closes in the canal. The inferior pair (sacral cornua) articulate with the horns of the coccyx. At each side of the 
median line are two grooves, pierced by the posterior sacral foramina, which are much smaller than the anterior, and transmit 
the posterior branches of the sacral nerves. 

The borders, or lateral surfaces of the sacrum, present two distinct parts, one superior, (iliac,) large and irregular, which in 
the fresh state is covered with cartilage, and articulated with the ilium ; the other inferior, thin, and narrowing to a point, gives 
attachment to the sacro-sciatic ligaments. A small indentation terminates this border, which, with the corresponding extremity 
of the coccyx, forms a notch for the transmission of the fifth sacral nerve. 

The base, or superior extremity, broad and expanded, presents, 1st, towards the middle line, an oval surface, cut off obliquely, 
and tipped with cartilage for its articulation with the last lumbar vertebra ; behind this is a triangular aperture marking the' 
orifice of the sacral canal. 2d, On each side a smooth convex surface, inclined forwards, and continuous with the iliac fossa ; an 
articular process, concave from side to side, which looks backwards and inwards, and receives the inferior articular process of the 
last lumbar vertebra. Before each articular process is a groove, forming part of the last intervertebral foramen, and behind them 
is a curved, sharp, and depressed border, which bounds the sacral canal, and therefore corresponds with the lateral arches of the 
vertebrae, and gives attachment to the last ligamentum subflavum. 

The apex, or inferior extremity, directed downwards and forwards, presents an oval convex surface, which articulates with 
the coccyx. 

The sacrum in its interior contains much loose spongy substance, and its exterior layer is but moderately compact. Its cen- 
tral part is also hollowed into a canal, (sacral,) which curves from above downwards as the bone does; hence it is of a triangular 
form, and gradually narrows as it descends. 

Attachments of muscles.— The sacrum gives attachment, by the lateral parts of its anterior surface, to the pyrainidales mus- 
cles ; by its posterior surface at each side, to the gluteus maximus, sacro-lumbalis, longissimus dorsi, and multifidus spina; ; by 
the inferior part of each border, to part of the coccygeus. 

Articulations. — The sacrum articulates with the last lumbar vertebra, the two iliac bones, and the coccyx. 

Developement.—ln the first three pieces there are found five bony points, one being in the body, two at the sides in front 
and two posteriorly in the arches. Analogy would lead us to admit two more in each body corresponding with its upper and 
lower surfaces, and one in the spinous process, in all eight. In the two lower false vertebra; there appear to be but three, one 
being in the body and one at each side. 

Ossa Coccygis.— These bones, (plates IV. VI. XIV.,) when united together, which is usually the case in advanced life, are 
supposed to resemble a cuckoo's bill, and are therefore called coccygeal, (*«***£, a cuckoo.) Most commonly there are four of 
them, sometimes but three ; in a few instances five have been found. They diminish gradually in size from above downwards, 
which gives them, when taken together, a pyramidal form. As they are placed in a continuous line with the inferior third of the' 
sacrum, they form a slightly concave surface anteriorly, a convex one posteriorly. 

The first of these bones resembles, in some measure, the last false vertebra of the sacrum. Its body is small and concave at 
its upper aspect, which articulates with the extremity of the sacrum ; posteriorly, two small processes, termed cornua, project, 
which rest upon the sacral cornua. The second bone of the coccyx is somewhat square, the third oblong, and the fourth a small 
rounded nodule of bone. 

Attachments of muscles.— The coccyx gives attachment to the gluteus maximus, and to the coccygeus of each side, and by 
its point to the sphincter ani. Its base articulates with the sacrum. 

Each of these pieces has a separate osseous centre. 

Os innominatum.—Tida bone (plates XIV. XV. XXIII.) is of so complex and irregular a form, that it bears no perceptible 
resemblance to any other known object, and therefore remains « unnamed" and unnameable. The two bones thus distinguished 



u ♦ i n* t>,n inferior and lateral parts of the trunk, extending from the sacrum forwards to the 
,,, fc nation of a name are sUua ted .the if erio an d ate a ^ ^ ^ ^ ^ fa ^^ them 

m ,., hall Hae, where they are connected togethe '. ™"*^ ^ transmit it to the lower extremities: thus placed, and being 

' " To Sat me description of this very irregular bone, it is convenient to consider separately each of the parts into which it 
ind divided in early life, viz. the ilium, os pubis, and ischium. 

The ,7,W (os ilii,) or iliac portion of the os innommatum, constitutes the upper part of the bone where it rs broad 
and expanded; it is situated at the superior and lateral part of the pelvis. Its surfaces, b.rders, and angles must be considered 

^Thc'external surface, (dorsum,) convex before, concave posteriorly, is marked by two curved lines running from before 
backwards • the superior one, commencing at the anterior-superior spinous process, arches downwards to the margin of the sacro- 
sciatic notch A space, narrowed before, and wider posteriorly, is included between the line just noticed, the margin of the crista 
ilii and the border of the rough surface for the attachment of the gluteus maximus ; from this space the gluteus medius arises. 
The inferior curved line is shorter and less strongly marked than the superior; it commences at the anterior-inferior spinous 
process, and inclines backward to the sacro-sciatic notch. The space between these lines gives origin to the gluteus minimus. 
On its 'posterior and superior part is observed a rough surface, which gives attachment to the gluteus maximus muscle. The 
internal surface of the ilium is divided into three parts. One anterior, smooth, concave, and of considerable extent, is called the 
iliac fossa ; the posterior one is rough and uneven, and serves for its articulation with the sacrum ; whilst the third is smooth. 
much smaller than the others, and is the only part that enters into a formation of the true pelvis. 

The superier border, {crista ilii,) extending from before backwards, is convex and arched; it forms an epiphysis in 
infancy, and is sometimes called the spine of the ilium, but more properly its crista ; its anterior extremity curves inwards, the 
posterior outwards. This border presents an external and internal lip, (labium.) and a rough interval, to each of which muscles 
arc attached. 

The anterior border, depressed and excavated, descends from the superior border or crista towards the os pubis, with which 
it is continuous : its junction with the crista is marked by a prominent point, called the anterior-superior spinous process; and 
that with the pubis, by an obtuse elevation, common to the two bones, called the ilio-pectineal eminence. This border presents 
two excavations, separated by a prominent point, called the anterior-inferior spinous process. The interval between the latter 
and the ilio-pectineal eminence gives transmission to the iliacus and psoas muscles; and that between the spinous processes trans- 
mits the external cutaneous nerve, and gives origin to some fibres of the sartorius. 

The posterior holder also presents two notches, separated by a prominent point of bone, called the posterior-inferior spinous 
process; above which is another bony eminence, called the posterior-superior spinous process: of the notches, the inferior and 
larger one contributes to form the sacro-sciatic notch. 

Of the three angles of the bone, the two superior ones correspond with the spinous processes, (anterior and posterior;) the 
inferior is represented by the constricted part of the bone. Here we observe three surfaces, (when the ilium is separated from the 
us pubis and ischium :) one external, smooth, concave, forming part of the acetabulum, the deep cavity which receives the head 
of the femur; one anterior, small and triangular, marking the junction with the os pubis; a third posterior, the junction with 
the ischium. 

attachments of muscles.— To the interval between the crista and the superior curved line on the dorsal surface is attached 
the gluteus medius; to the space between the curved lines, the gluteus minimus; to the posterior rough surface, the gluteus 
maximus; to the internal surface, or iliac fossa, the iliacus muscle. 

To the anterior half of the external lip of its crista is attached the obliquus externus abdominis; to the posterior third of the 
same up, the latissimus dors,; to the anterior two-thirds of the interval between the lips, the obliquus internus; and to the 
remainder, the erector spin* ; to the anterior three-fourths of the inner lip, the transversalis abdominis ; to the posterior fourth 
ol the same lip. the quadratus lumborum. 

To the external surface of the anterior-superior spinous process is attached the tensor vagina, femoris ; to the process and the 
notch beneath it, the sartorius ; to the anterior-inferior spine, the straight tendon of the rectus femoris; and to the brim of the 
tabulum, the external tendon of that same muscle. 

•/" / ;:'" ; / ': //0 '!!r Tll i S b ? ne arli f ula,es with the sacrum > «* i°ms by bony union with the os pubis and the ischium 
Os Pubis.— The pubic bone p ate XXIII.) forms the anterior and \ nnor „„,* c .. • iscnium. 

into two portions one snnerior an, thiel- ti!Z t u Ta I T P " ° f tlie 0S 1M °i™atum ; and is usually divided 

into tu o portions, one supenor and thick, called the body, the other inferior and thin, the ramus 

The body, horizontal in its direction, presents three surfaces senantPH W thL Q 
slightly depressed, is covered by the pectineus muscle; the 2ZlsZot ^ f ? f ^ ^ ^^ "^ 

or inferior is somewhat grooved transversely, overhand IL^^ZT^n^ 1 T T ^ ^ Pel ™ ""** 5 *" ^^ 

The external extremity of the bone is thick and pr sents Z ^ ' "* ' ° ks downwards to the top of the thigh. 

■ek, and presents three faces; one, concave, forms part of the acetabulum; another, 



63 

superior, connects it with the ilium, (the junction being marked by a rounded elevation, called the ilio-pectincal eminence;) the 
third, inferior, is joined with the ischium. The internal extremity, flat and compressed, is joined to the corresponding part of the 
opposite bone by an intervening cartilage, the junction being termed the symphysis pubis, (avn<pv/xi, to grow together.) Leadin°- 
outwards from the symphysis, whose direction is vertical, may be observed another margin, nearly an inch in length, which is 
placed horizontally, and named the crista. The angle formed by the crista and symphysis is termed the angle of the pubes ; the 
crista is terminated externally by a projecting nodule of bone — the tuberosity or spine, from which runs outwards a sharp line, 
(ilio-pectineal line,) giving attachment to Gimbernat's ligament and to the pectineus muscle, and marking the margin or upper 
boundary of the true pelvis. 

The ramus, or branch of the bone, inclines outwards and downwards from the body, forming an angle with it, becomes 
thin, and unites with the ascending ramus of the ischium. Its inner surface is smooth ; the external is rough, for the attachment 
of muscles. One of its borders, thick and rough and somewhat everted, forms with the opposite bone an arch, called the arch of 
the pubes; the other border, sharp and thin, forms part of the margin of the obturator foramen. 

Attachments of muscles. — To the crista are attached the pyramidalis and rectus abdominis ; to the tuberosity and anterior 
surface, the obliquus externus ; to the pectineal line, the pectineus and Gimbernat's ligament ; to the crista, and part of the same 
line, the obliquus internus and transversalis. 

To the external surface, at the angle, the adductor longus ; to the space between this and the border of the obturator foramen, 
the adductor brevis ; to the line of the symphysis and the ramus, the gracilis ; and to the whole margin of the foramen, the obturator 
externus. To the inner surface, part of the obturator internus and levator ani. 

Ischium. — The ischium (plate XXIII.) forms the posterior and lowest part of the os innominatum ; it consists of two parts, 
a body and a ramus, united at an angle, so as to give the bone somewhat the figure of a hook. The body, or larger part, short, 
thick, and somewhat triangular in form, presents three surfaces or aspects which look in different directions; there are three 
borders and two extremities. On its external surface may be observed a smooth concave part, which forms more than two-fifths 
of the acetabulum, and is surrounded' by a curved prominent line, which forms the lower border of that cavity ; beneath this is a 
groove, directed horizontally backwards, corresponding with the tendon of the obturator externus muscle ; and still lower a rough 
line, which bounds the tuberosity of the ischium, and gives attachment to the quadratus femoris. The external surface of this 
portion of the bone is smooth, and forms part of the cavity of the pelvis. This is broad at its upper part, as it comprises the 
interval between the spine, or spinous process, and the margin of the obturator foramen. Below this process it becomes narrowed, 
constricted, and rounded off at its back, so as to form a pulley-like surface in the interval between the spine and the tuberosity 
where the obturator internus muscle winds round its border. The posterior surface, broad at its upper part where it comprises 
the space between the spine and the margin of the acetabulum, then becomes narrowed and depressed, finally ends in a rough and 
rather prominent surface bounded by well-defined borders, which is the tuberosity of the ischium. 

The tuberosity, (tuber ischii,) thick and rounded, forms the part on which the body is supported in the sitting position. 
This rough prominence presents three impressions upon it, corresponding with the points of attachment of the three long flexor 
muscles of the leg. 

The superior extremity of the bone (if it be examined in early life, when the bone can be detached from the ilium and os 
pubis, or after a section has been made of the os innominatum, so as to divide it into its three parts,) presents three surfaces, of 
which two are flat and triangular, and mark its junction with the ilium and os pubis ; the other, concave and smooth, forms part 
of the acetabulum. The inferior extremity of the body of the bone is identified with the tuberosity. The ra?nus of the ischium 
is the flat, thin part, which ascends forwards and inwards from the tuberosity, towards the ramus of the os pubis with which it 
is united. One margin of the ramus, thick, rough, and somewhat everted, forms part of the inferior outlet of the pelvis ; the 
other, thin and sharp, bounds the obturator foramen ; its external surface looks outwards and downwards, is rough for the attach- 
ment of the muscles ; the inner surface forms part of the lower circumference of the pelvis. 

Attachments of muscles. — To the outer border of the tuberosity and the contiguous part of the ramus, the adductor mag- 
nus ; to the inner margin of the tuberosity at its fore part, the erector penis ; to the adjacent margin of the ramus, the transversus 
perins&i ; the internal obturator muscle to the inner surface of the bone behind the thyroid or obturator foramen. 

To the posterior surface of the tuberosity, the three flexors of the leg, scil. the biceps, semitendinosus, and semimembranosus; 
to the rough line on the outer surface which bounds the tuberosity, the quadratus femoris ; to the external surface of the spine, 
melius superior; to the adjacent border of the tuberosity, the gemellus inferior; to the internal surface of the bone, the 
levator ani ; and to the spinous process, the coccygeus. 

Developement. — The three pieces which form the os innominatum commence each with a separate point of ossification, and 
I he extension of the osseous deposit proceeds in each towards the acetabulum as a common centre, so that when completed it is 
found to consist of a portion of each. Besides these, the spine of the ilium and the tuberosity of the ischium are lunar. I 
separately. 

Acetabulum. — At the junction of the three pieces of the os innominatum is situated the cavity which articulates with the 



4 ,l,o f.-mur. It is called acetabulum, also the cotyloid or cup-shaped cavity, (»**» a cup ; „So 5 , like >.) Of this the 
,,,„„„ forms somewhat more than two-fifths, the ilium somewhat less thau two-fifths, the remainder being made up by the os 
' ,„s I, is surrounded in the greater part of its extent by a margin or supercilium, which is most prominent towards the superior 
' „d external part- but at the opposite point, or towards the obturator foramen, it is deficient, leaving a notch, {cotyloid notch, 
Bometimes also called incisura acetabuli.) The greater part of the cavity is covered with cartilage in the natural condition; but 
towards the notch there is a part depressed beneath the rest, and which corresponds with the passage of the round ligament, and 
some synovial crvptac : this has no cartilaginous coating. 

When we examine the pelvis as a whole, we observe that these articulating cavities, placed in the lateral walls of the pelvis, 
l,,uk outwards and forwards, and that they rest, when the body is erect, upon the globular heads of the thigh-bones, which they 
lodge The margin of each cavity is rough and uneven ; but in the recent state it is rendered smooth, and the depth of the 
is increased, by a fibro-cartilagiuous rim, which runs round it, and increases its depth. Where the osseous margin is defi- 
ctent, (at the cotyloid notch,) its place is supplied by a fibrous band, so stretched across as not altogether to fill it up, but rather to 
bridge it over, leaving a space beneath it for the entrance of vessels into the interior of the joint. 

To ili" inner side of the acetabulum is found, in the dried bone, a large aperture, which, however, in the natural condition, 
is almost completely closed by a fibrous membrane. It is called foramen obturatorium, perhaps more properly obturatum, 
from tli'' circumstance of its being closed by a membrane or ligament. It is also called foramen thyroideum (shield-shaped; 
9«p,oj, a shield) from its shape; and not unfrequently foramen ovale. It is somewhat of an oval form in the male, its greatest 
diameter being extended obliquely downwards and outwards; in the female it is a three-sided figure with rounded angles. 

Qtneral confirmation of the Pelvis. — The pelvis, or basin-shaped cavity, which is thus made up of the ossa innominata, 
the saci inn, and coccyx, deserves to be attentively examined, not merely as to the details of the parts which compose it, but as to 
us general conformation. Taking the objects which are deserving of notice on the external surface, from before backwards, and 
beginning at the median line, we observe the symphysis pubis, or the line of junction between the two bones of that name; its 
direction is vertical, its depth greater in the male than in the female ; beneath it is an angular space, the pubic or sub-pubic arch, 
bounded by the rami of the ossa pubis and ischia at each side. On each side of the arch is the thyroid or obturator foramen 
above noticed, and still more laterally the acetabulum, above which rises the broad convex part of the ilium, (dorsum ilii.) Pos- 
teriorly, along the middle line, are situated the tubercles or spinous processes of the sacrum; external to these, the posterior sacral 
foramina, and next, a broad) unequal surface, to which the sciatic ligaments and gluteus maximus are attached; and lastly, the 
large deep excavation (sacro-sciatic notch,) bounded by the margins of the sacrum and os innominatum. 

The internal surface is divided into two parts by a prominent line, (linea ilio-pectinea,) leading from the tuberosities of the 
ossa pubis, outwards and backwards, to the prominent point of the sacrum, (promontorium.) This constitutes the margin or 
brim of the true pelvis, all the part above it being called the false pelvis; as in reality it belongs to the abdomen. 

The superior circumference of the false pelvis is formed on each side of the crista ilii ; posteriorly may be observed a deep 
notch, which is divided into two parts by the base of the sacrum, and anteriorly (in the interval between the anterior-superior spinous 
processes of the ilia) the margin of the bone subsides, so as to present a deep excavation, which in the natural condition is filled 
up by the soft parietes of the abdomen. Along this margin are placed the anterior-inferior spinous processes of the ilia, the ilio- 
pectineal eminences, the spines or tuberosities of the ossa pubis, with their cristae and angles.* The inferior circumference or outlet 
ot the pelvis presents three bony eminences, (the tuberosities of the ischia on the sides, and the coccyx behind in the middle line ) 
These are like so many promontories, separated by deep excavations. The anterior one, (pubic arch,) triangular in its form, is 
bounded on each side by the rami of the ischia and ossa pubis, extending upwards and inwards, from the tuberosities of the 
.soh.a to the symphysis pubis. The two other notches (sacro-sciatic) are placed behind and above the tuberosities, and corres- 
pood with the interval between the sacrum and os innominatum. When examined in the dried bones, their extent is consider- 
able ; but m the natural condition they are divided into lesser spaces by the sacro-sciatic ligaments 

smo Jh ™7hetnT f ° r r i0n * T ^ ^ 7" T^ 7 " *' tW ° ^ In the female the bones are thinner, more 
smooth on the surface, the muscular impressions being less strongly marked, and, though its perpendicular depth is less its 
breadth and capacity are greater. The ala3 of the iliac bones are more expanded • thP nn Jr „n f PerpenQ1CUlar de P m 1S ess ' " S 
Paction of the sacrum less perceptible; and the space between *?23£ l^T "£ZM£ 
physis pubis is less in the female than in the male, whilst the breadth of the pubic arch is greater 

In the erect attitude of the bodv, the direction of the Delvis is nhlim,o iL . • • 

», that if a line be drawn from the upper border of 'he symphvs ™Tk I T "T""' be " ,g '" C ' ined f °" VaraSi S ° ""* 
.1... bone. In eonsequence of ,his mclLion, ,he emraTZe "„ a ris / £ ?," t% "" T' * "*" agai " St ' he midd ' e ° f 
■ be former, ,f drawn from above •nmm^mlttlZ££££ l "' ""J™,™ 7 ^"^ ^ ttot ° f '" e "**'• 
and upwards, tonehes the promontory of ,he saemm bo h I fore d ' * ^ " ^^ {l ° m be '° W ' h*"*™* 

d.deren, dimensions of t be maie and flmaie p££'JE ^£^£5^,^^ •- Pe ' Vi ° ^ ^ 

• The superficial depression of this margin of bone, just at the outside of the nprti 1 
ilium, has been pointed out by T. D. Mutter, M.D., Prof. Sum in Jeffers M d' 1 T ' protuberance > and between the anterior spinous processes of the 

femoris, (directly upwards,) which he has described in the 51st Nn JthlVh^ -!°i i! !!? S ?.' ™ the Site ° f the head of the bone in a * ixth luxation of the os 

ww. 01 me Philadelphia Medical Examiner.— J. P. 



65 







Meckel. 


Cloquet. 


Burns. 


In the Male Pelvis. 


In the Female Pelvis. 


Female. 


Female. 


inch, lines. 


inch. lines. 


inch, lines. 


inch, lines. 


Between the anterior-superior spinous processes of the ilia . 




7 8 


8 6 


10 


10 


Between the middle points of the cristse of the ilia 


, 


8 3 


9 4 


11 1 


11 1 


The transverse diameter } 


r 


4 6 


5 


5 6 


5 6 


The oblique . C of the inlet 


) 


4 5 


4 5 


4 7 


5 5 


The antero-posterior . J 


I 


4 


4 4 


4 4 


4 


The transverse diameter } 


c 


4 


4 8 








The oblique . . C f the cavity 


) 


5 


5 4 





— 


The antero-posterior . j 


I 


5 


4 8 


— 


— 


The transverse . } « , . 
The antero-posterior . 5 of the outlet 


i 


3 
3 3 


4 5 
4 4 


4 4 
4 4 


4 

4 


The last may be increased to five 


inches in consequence of the mobility of the 


coccyx. 





Bones of the Lower extremity. — The lower extremity is made up of three parts: the thigh, leg, and foot. 

The osseous part of the first consists of one bone — the femur ; that of the leg, of two — the tibia and fibula. The adjacent 
extremities of these, together with the patella, (a sort of sesamoid bone,) form the knee. 

The foot is composed of three parts, the tarsus, metatarsus, and phalanges. 

The Femur. — The femur or thigh-bone, (plate XXIV., os femoris,) the longest bone of the skeleton, is situated between the 
pelvis and the tibia. In the erect position of the body, its general direction is not vertical ; it gradually inclines inwards towards 
the lower part, so that the bones of opposite sides, though separated at a considerable distance where they are connected with the 
pelvis, approach each other inferiorly, and come nearly in contact. The degree of this inclination varies in different persons, and 
is more marked in the female than the male. The femur presents a central part, or body, and two extremities. 

The body, or shaft, as it is sometimes called, compressed, but nearly cylindrical towards the centre, and at the same time 
slightly convex or arched forwards, is expanded superiorly and inferiorly. Its anterior surface, convex and smooth, is broader to- 
wards the lower than the upper extremity. Both its lateral surfaces are compressed and somewhat fiat ; but it may be observed 
that the external is somewhat concave ; it affords attachment to the vastus externus muscle. The surface, which superiorly looks 
inwards, is, in the lower third of the bone, inclined somewhat backwards, and gives attachment to the vastus interims. The an- 
terior surface is separated, though not in a very marked degree, from the lateral surfaces by two lines, which may be traced 
upwards from the condyles towards the superior extremity of the bone; but posteriorly, at the union of the two lateral surfaces, 
is a rough and prominent line, {linea aspera,) which gives attachment to several muscles. 

The Linea aspera, is most prominent towards the centre of the bone, and when examined with attention, presents two mar- 
gins and a rough interstice, each giving attachment to muscles. Above and below the centre, it subsides as it were towards the 
extremities, and also becomes bifurcated. The two superior divisions or branches of the line terminate, the one (internal and 
somewhat shorter) at the lesser trochanter; the other, external, at the greater trochanter ; in the course of the latter a rough 
strongly-marked impression exists, which gives insertion to the gluteus maximus. The inferior divisions spread more asunder, 
and terminate at the condyles, enclosing between them and the margins of these prominences, a flat triangular portion of the bone, 
which corresponds with the popliteal vessels. Towards the superior part of the linea aspera may be observed a foramen directed 
from below upwards/which transmits the medullary vessels. 

At the superior extremity of the bone is placed its neck, which is directed upwards and inwards, so as to form an obtuse 
angle with the body or shaft ; at its point of union with the latter are two eminences, {trochanter, major and minor,) one on the 
outer, the other on the inner side ; it is from between these that the neck arises. 

The Trochanter major is prolonged from the external surface of the body of the bone, and nearly in a line with its axis. 
This apophysis, quadrilateral in its form, is convex and rough on its external surface, which is marked by a line directed obliquely 
downwards and forwards for the attachment of the gluteus medius; the internal surface, of less extent, presents at its base a pit, 
{trochanteric or digital fossa,) which receives the external rotator muscles ; its superior or terminal border is flat and straight? 
and the posterior thick and rounded. At the posterior aspect of the great trochanter may be observed an oblique and prominent 
line, directed downwards and inwards, and terminating in the trochanter minor. 

The Trochanter minor, a conical rounded eminence, projects from the posterior and inner side of the bone, and gives attach- 
ment to the tendon of the psoas and iliacus muscles. 

The neck of the femur, which is so named from its constricted appearance and supporting the head, forms an obtuse angle 
with the body of the bone ; it is compressed from before backwards, so that its diameter in this is much less considerable than in 
the vertical direction, in which greater power of resistance is required for sustaining the weight of the body ; its anterior surface 
is broad and smooth ; the superior, inclined upwards, is short and somewhat concave ; the inferior is the most extensive. The 
union of the neck with the rest of the bone is marked by the trochanters and two intervening oblique lines, {inter-trochanteric,) 
of which, the anterior one is rough and but slightly prominent ; the other, situated posteriorly, forms a smooth projecting ridge, 
which overhangs the trochanteric fossa. 
TJones. — o 



66 

, , , u- u c^nc g p™ side cable segment of a sphere, is tipped with cartilage in the 

- nsacsu - - -- — -- ttttsRtzzs by ,wo em,nences ' *" 

temal lateral ligament of the knee-joint oth ^ ^ . g rather &pparent than rea]> 

^'^r^'W.ira^Sta".^ are brought to the same plane. The internal condyle 
J^^K^E ^tt^ent to the mternal lateral ligament of the knee-joint and the tendon of the 
aZc^rn^ In the fossa, between the condyles, posteriorly, are implanted the crucial ligaments. 

T a"uclr surfaces of b th condyles, covered with cartilage in the fresh state, are united anteriorly where they form a 
poUev 1 k rfl, concave from side J side, on which the patella glides. Infenorly, these surfaces diverge as they pass back- 
wis and -hen they terminate at the posterior surface of the bone, are separated by a considerable interval. 

;;" .'/"/;1,-Thc femur articulates superiorly with the acetabulum; by its condyles with, infenorly, the tibia, and, 

^Ma'e^Tofmuscleto-To the anterior surface, the crureus; to the two lateral and to both lips of the linea aspera are 
rtlached the vastus internus and externus; to the centre of that line, the adductors and the short head of the biceps flexor; to the 
superior border of the trochanter major, the gluteus medius; to its anterior border, the gluteus mining; to the fossa, at its poste- 
rior surface, the external rotators ; to the lesser trochanter, the tendon of the psoas and iliacus ; to the line between the trochanters, 
posteriorly the quadratus femoris ; to the line below the lesser trochanter, the pectineus ; to the rough impression beneath the 
great trochanter, the gluteus maximus; just above the inner and outer condyle, the corresponding heads of the gastrocnemius; to 
the external condyle, the plantaris; to the fossa beneath the external tuberosity, the popliteus. 

Developement— The femur grows from five osseous centres ; one being in the middle of the shaft, which appears very early; 
the two trochanters and the head commence by separate points; and there is one at the lower extremity, which is evolved into 

the two condyles. . . 

The Patella.— The patella (plate XXIV., ro/ula, knee-pan) is situated at the anterior part of the knee-joint, being attached 
by a ligament {ligamentum patelhe) to the tibia, so that its position with regard to the joint varies according to the movements 
of that bone. Compressed and somewhat triangular in its form, its anterior surface is convex, and covered by the expanded fibres 
of the extensor tendons ; the posterior, smooth and covered with cartilage for its articulation with the condyles of the femur, is 
divided into two parts by a vertical line, the external being the broader. Beneath these is situated a small irregular depression, cor- 
responding with the apex, or narrowest part of the bone, which gives attachment to the ligamentum patellae. The superior 
extremity, broad and rounded off at its margin, gives attachment to the extensor muscles; the inferior, narrow and pointed, to the 
ligament already named ; the lateral borders are convex, the external being thinner than the internal. 

The Tibia.— The tibia, (plate XXVI.,) next to the femur, is the longest bone in the skeleton ; situated at the anterior and 
inner side of the leg, it alone receives from the femur (under which it is placed vertically) the weight of the trunk, and communi- 
cates it to the foot. Like the other long bones, it is divided into a body and two extremities. 

The superior extremity, much thicker and more expanded than any other part of the bone, (being proportioned in size to the 
lower extremity of the femur,) is broader from side to side than from before backwards; its circumference is somewhat rounded 
and convex in front and at the sides, but slightly hollowed posteriorly ; at the fore part, a little below the head, is situated an 
eminence, sometimes called the anterior tuberosity, more properly the tubercle, which is somewhat rough at its lower part, for the 
attachment of the ligament of the patella, and smooth superiorly, where it corresponds to a small synovial bursa, intervening 
between that ligament and the bone. On the sides, and above this, are two rounded eminences, {tuberosities,) the external one 
lienm somewhat smaller than the other, and marked posteriorly by a flat surface, which articulates with the head of the fibula; 
tinse processes give attachment to the lateral ligaments of the knee-joint. On the superior aspect of this portion of the bone may 
be observed two concave cartilaginous surfaces, {condyles,) which sustain the condyles of the femur ; the internal one is some- 
what the deeper, its greatest diameter is from before backwards; the external one is nearly circular. In the interval between the 
articular surfaces is situated a pyramidal eminence, the summit of which is usually divided into two tubercles; it is named the 
spine or spinous process of the tibia; before and behind this are two irregular depressed surfaces, which give attachment to the 
crucial ligaments and to the semi-lunar cartilages. 

The lower or tarsal extremity of the bone is much smaller than the upper, and nearly quadrilateral in its form; the anterior 
surface, convex and smooth, is hounded below by a slightly rough margin which gives attachment to the anterior tibio-tarsal 
ligament ; the posterior is flat, and marked by a groove for the flexor longus pollicis ; the external, slightly concave, is rough 



C7 

superiorly, for the attachment of the transverse ligament, and smooth below, to receive the extremity of the fibula. From the 
inner border of this end of the bone projects downwards a triangular apophysis, the internal malleolus ; the inner surface of 
which is convex, and covered merely by the skin, the external is smooth, and articulates with the side of the astragalus ; the 
anterior forms a rounded border, whilst the posterior is marked by two grooves for the tendons of the tibialis posticus, and flexor 
longus digitorum ; to the most dependent part of the process is attached the internal lateral ligament. The lower articular sur- 
face of the tibia, or that part which enters into the formation of the ankle-joint, consists of two parts, one vertical, just described 
as being situated at the outer side of the malleolus ; the other horizontal in its direction, concave and quadrilateral in its form, 
divided into two parts by a slightly raised line ; of these two surfaces, which are united at a right angle, and tipped with cartilage 
in the fresh state, the latter rests on the dorsum of the astragalus, the former is applied to its inner flat border. 

The body of the tibia, triangular in its form, diminishes gradually in size for about two-thirds of its length, after which it 
increases somewhat towards its lower extremity. The internal surface is convex and subcutaneous, except at the upper part of 
its extent, where it is covered by the tendons of the sartorius, semi-tendinosus, and gracilis muscles. The external surface, 
slightly hollowed above, where it gives origin to the tibialis anticus, is convex, and somewhat inclined forwards below, where it 
is covered by the extensor tendons. The posterior surface is very deeply seated ; not so uniform in its outline as the others, it is 
marked at its upper third by a line extending upwards and outwards to the external tuberosity ; the part above this is triangular, 
and gives attachment to the popliteus muscle, that below it to the tibialis posticus and flexor digitorum, and from the line itself 
arises the soleus. Near this line may be observed a medullary foramen of large size, whose direction is from above 
downwards. 

The surfaces here indicated are separated by an equal number of borders. The anterior border, more or less sinuous in 
direction, sometimes considerably curved, is for the most part subcutaneous; sharp and prominent, especially towards the middle, 
and hence named the crista or spine of the tibia, it subsides towards the lower end of the bone, as if to allow a smooth surface 
for the passage forwards of the vessels and muscles, which superiorly are placed on the outer side. The inner border, thick and 
rounded, gives attachment to the soleus and flexor longus digitorum ; whilst the external, somewhat sharp, divides inferiorly into 
two lines, which diverge towards the surface of articulation with the fibula. The interosseous ligament is inserted into this 
external border. The body of the tibia is slightly twisted, so that the internal tuberosity inclines a little backwards, and the 
internal malleolus forwards, which conformation deserves attention in the diagnosis and adjustment of fractures. 

Articulations. — The tibia articulates with the femur, the fibula, and the astragalus. 

Attachments of muscles. — To the external surface and external tuberosity, the tibialis anticus ; to the latter also, the head 
of the extensor longus digitorum ; to the inner surface, the sartorius, gracilis, semi-tendinosus, and semi-membranosus ; the 
popliteus, to the triangular space on the posterior surface ; the soleus, tibialis posticus, and flexor longus digitorum, to the rest of 
its extent, and, through the medium of the patella and its ligament, it may be said to give insertion to the extensors of the leg. 

Developement. — There is an osseous centre in the body of the bone, and one at each extremity. 

The Fibula. — This bone (plate XXVI., fibula, perone, xcpovr;, a clasp) is situated at the external side of the leg ; it is 
nearly equal to the tibia in length, but is much more slender. When the fibula is placed beside the tibia in its natural position, 
its lower extremity will be found a little farther forward than the upper one, and its shaft inclined backwards and a little inwards, 
so as to be convex in that direction. 

The body of the bone, irregularly triangular in its form, presents three prominent lines bounding three surfaces; the anterior, 
or most prominent line, gives origin to muscles in the superior part of its extent, and bifurcates towards its lower extremity, so 
as to enclose a slightly concave triangular surface, which is subcutaneous; the internal one also gives attachment to muscles, and 
inferiorly, where it inclines forwards, to the interosseous ligament. The internal surface looks backwards for about a third of its 
extent, and somewhat forwards in the rest, and is divided, but unequally, into two parts, by a slightly-marked longitudinal line, 
to which the interosseous ligament is attached for about two-thirds of its length ; the part of the surface behind this is grooved, — 
it gives attachment to the tibialis posticus muscle ; the anterior portion, the smaller, to muscles placed in front of the leg. The 
external surface, concave in the greatest part of its extent, gives origin to muscles; — towards its lower extremity, this surface is 
inclined backwards, conforming with the peronei muscles, which are connected with the superior part of the bone, and incline in 
that direction to pass behind the external malleolus. The posterior surface, convex and smooth, affords attachment to muscles, 
and presents towards its middle a small foramen, directed obliquely downwards for the transmission of the medullary vessels ; ir 
the lower part it inclines inwards, and is terminated by a rough surface connected with the tibia. 

The superior extremity of the bone, called also the head, is smaller than the inferior one ; it presents on the supero-internal 
part a small oval and nearly flat surface, for its articulation with the corresponding part of the external tuberosity of the tibia ; 
the remainder is unequal, and gives insertion to the biceps flexor cruris, to the external lateral ligament of the knee-joint, and to 
those which connect the tibia and fibula. The inferior or tarsal extremity forms the external malleolus, whirl) is longer and 
more prominent than the internal one; in front it receives the insertion of ligaments; behind is situated a shallow groove traversed 
by the tendons of the peronei muscles; the outer side is convex and subcutaneous ; the inner presents a small triangular surface, 
•xmvex in the perpendicular, and nearly plain in the antero-posterior direction, which articulates with the astragalus, and is 



68 

bounded posteriorly by a rough depression, affording attachment to the transverse ligament of the ankle-joint, whilst the apex 

eives origin to the external lateral ligament. . . 

.*r/L/«/»>H,.-The fibula articulates at both extremities with the tibia, and at the inferior one with the outer border of the 

Z/nnents of muscles.-The internal surface, by its anterior portion, to the extensor communis digitorum, extensor pro- 
prius pollicis. and peroneus tertius; by the depression on its posterior part, to the tibialis posticus: the external surface, to the 
J,,,,,,, i; the posterior surface, to the soleus and flexor longus pollicis; its head, to the biceps flexor cruris. 

Developement.— The fibula has an osseous centre for its body, and one for each extremity. 

/innes of the fool. —The foot is composed, like the hand, of three parts, viz. the tarsus, metatarsus, and toes. 

Tarsus.— The tarsus is composed of seven bones, viz. the os calcis, astragalus, naviculare, cuneiforme internum, cuneiforme 
medium, cuneiforme externum, and cuboides. 

The Caleaneum.— This bone (plates XXVIII. XXIX., os calcis— calcaneum) is situated at the posterior and inferior part 
of the tarsus, and forms the heel by its projection backwards ; elongated in that direction, and compressed laterally, it is the 
largest of the bones of the foot. Superiorly it presents (taking the objects successively from behind forwards) a concave portion, 
intervening between the insertion of the tendo Achillis into its posterior border, and the surface which articulates with the astra- 
galus; then the last-named surface, which is bounded by a rough depression for the insertion of a ligament, (interosseous;) and 
lastly a narrow concave surface, which also articulates with the astragalus. On the inferior surface, which is narrower than the 
preceding, and broader behind than before, are observed posteriorly two tubercles, (the internal being the larger,) serving for the 
attachment of the plantar fascia and the superficial plantar mnscles ; between them a depression for the origin of the long plantar 
ligament, and in front another eminence, giving attachment to the inferior ligament (calcaneo-scaphoid) connecting this bone with 
the scaphoid. The anterior surface, the smallest, is slightly concave, and articulates with the cuboid bone. The posterior sur- 
face, convex, presents, inferiorly, inequalities, for the attachment of the tendo Achillis; and, superiorly, a smooth surface, sepa- 
rated from that tendon by a synovial bursa. The external surface, broader behind than before, presents in the latter direction, 
superficial grooves, for the tendons of the peronei muscles, and is subcutaneous in the rest of its extent. The inner surface, deeply 
concave, is traversed by the plantar vessels and nerves, and the tendons of the flexor muscles. A groove runs along at its upper 
edge, and under the tubercle which surmounts it, for the tendon of the flexor longus pollicis. The calcaneum articulates with 
the astragalus and the cuboid bone. 

Tht Astragalus, (ajrpayaxoc, a die.) — The astragalus (plates XXVIII. XXIX.) is situated at the superior part of the tarsus; 
its form is irregular, it appears as if twisted on itself. The upper surface presents, in front, a rough and slightly excavated part, 
serving for the attachment of ligaments; and behind it a large convex cartilaginous surface, which is longer and more prominent 
on the outer than on the inner side, broader before than behind, and articulated with the lower extremity of the tibia. On the 
outer and inner sides are situated two smooth surfaces, (the former the larger,) which are continuous with the preceding, and arti- 
culated with the inferior extremities of the tibia and fibula, (the malleoli.) On the inferior surface are observed, in front, and 
somewhat internally, a narrow convex surface, and behind, a broad concave one, both articulating with the os calcis; these are 
separated by a groove, which receives the ligament that proceeds upwards from the last-named bone. The anterior surface, con- 
vex, is received into the hollow in the scaphoid bone ; it is called the head, and the constricted part by which it is supported, the 
neck of the astragalus. The posterior surface, or rather border, is grooved and traversed by the tendon of the flexor longus 
pollicis. The astragalus articulates with the tibia and fibula above, with the os calcis below, and with the scaphoid in front. 

The Cuboid bone.— This bone (os cuboides, cuboidcum) (plates XXVIII. XXIV.) is situated at the external side of the 
tarsus ; its form is ind.eated by its name. The superior surface, rather rough, inclined obliquely outwards and upwards, gives 
attachment to ligaments. The inferior surface presents, in front, a depression traversed by the tendon of the peroneus longus 
muscle, m the middle a transverse ridge, (tuberosity,) and behind it an irregular surface, both of which give attachment to the 
calcaneocuboid ligament ; the former also to some fibres of the ligamentum longum plants. At the anterior aspect of the bone 
is a smooth surface, directed from without inwards and forwards, and divided into two parts, the internal one being square, the 
external triangular, and articulated, the former with the fourth, the latter with the fifth metatarsal bone ; at the posterior is a sur- 
face by winch it articulated with the os calcis. The external border, which is short and rounded, presents a groove, continuous 
with that on the inferior surface, and serving for the transmission of the t^nrl™ „f ,u„ i , n , . i 

, , , , ' ° ucuibimssion 01 tne tendon of the peroneus longus muscle. On the internal 

surface may be observed, towards its middle an elongated smnnth -,„/! *,„ 1 a . , . , . , 

f nm . „ ,.„..,' , . . . . , .' n elon s atea smooth and nearly flat portion, which articulates with the third cunci- 
iorm bone, the part betore and behind it being rouah for the attnehrrmm „fi; , Tl , . , . , ,,•>., 

•„„l fifth „,„„",, ,_„_ ir • , , s I = ' attachment of ligaments. The cuboid articulates with the fourth 

and tilth metatarsal bones before, with the os calc s hehinrl witV> th a ^* 1 - r 

Th, ».„„*„ ■ / a tv. u T , ' external cuneiform, and sometimes with the scaphoid. 

lhe Scaphoid bone.— The scaphoid or navicu ar bone, folates XXVTTT yyty \ j r ■> r 

navis , is nlnrwl nt th P innor Kn«t n /«f .1 e . v 7 ^ P AAV 111. XXIX, so named from its excavated form, ow^, 

»onA,j is placed at the inner border of the foot, between the astrapnlnQ nnri tv, -r x. T <- 

whirl, lonkq h-nW,*^ -, i , • , • asuagalus and the cuneiform bones. It presents a concave surface 

", r, i, "'I' ", tUr " Cd f ° nVardS - " S im "* «"*> P"*"* ■» *• &™ f » "Aercle toward 

o , , , '. ' T 7 ""'" Sl "' fa 7 ,re i,K ' q,U,li ' i,;s (or " lc "'^ment of ligame.us.-behind, a concavity for 

l.c.«l of lhe a s ,r.,,.alu,-„, hu ,„, „, rt , dlslIDCt surface , for ^^ ^ ^ ^ ^S > . Y 



69 

border is the prominence or tubercle, above noticed, which gives attachment to the tibialis posticus muscle ; on the outer side, in 
some instances, is a small articular surface, by which it is united to the cuboid bone. It articulates with the three cuneiform bones, 
with the astragalus, and sometimes with the cuboid. 

The Cuneiform bones. — These bones (plates XXVIII. XXIX., ossa cuneiformia, wedge-shaped) constitute the anterior 
and inner part of the tarsus ; the name expresses their form. In number three, they are distinguished by their numerical order 
from within outwards. The first is the largest, and has its base or broad border turned down into the sole of the foot, — the 
second, or middle, the smallest. The base, or broad border, of the second and third is at the upper or dorsal surface of the foot, 
and contributes to give it its arched form. They articulate behind with the navicular, and in front with the first, second, and third 
metatarsal bones. In consequence of their excess in length over the second, the first and third, in addition to articulating laterally 
with the corresponding sides of that bone, are in apposition with the base of the second metatarsal bone, which is inserted between 
them. The inner side of the first is subcutaneous, and the outer side of the third articulates by a smooth flat surface with the 
cuboid, and by a small linear facette with the fourth metatarsal bone. 

Attachments of muscles. — The os calcis, by its dorsal surface, to the extensor brevis digitorum pedis ; the inferior half of 
the posterior surface, to the common tendon of the gastrocnemius and soleus, {tendo Achillis,) and to that of the plantaris ; the 
inferior surface on the inner side, to the flexor accessorius, and part of the abductor pollicis ; on the outer side, to the abductor 
digiti minimi ; and between the two abductors, to the flexor brevis digitorum. 

The cuboid bone, by the inferior surface, to a portion of the adductor pollicis. 

The scaphoid bone, by its tuberosity, to a portion of the tendon of the tibialis posticus. 

The cuneiform bones. The first, by its base, to portions of the tendons of the tibialis anticus and posticus, and the second 
and third to part of the flexor brevis pollicis. 

Developement. — These bones have each a separate centre of ossification. The os calcis has a second in its posterior part or 
tuberosity. 

The Metatarsus. — The second or middle portion of the foot (plate XXVIII.) is analagous to the corresponding portion of 
the hand, (metacarpus,) and like it is composed of five bones placed parallel one with the other. They are named according to 
their numerical order, from within outwards. The first, or that supporting the great toe, is the shortest, but it exceeds all the 
others very considerably in thickness. The second is the longest, and the rest decrease successively in length. In all, the thick- 
ness of the extremities, particularly of the tarsal ends, is greater than that of the bodies. The bodies of these bones, elongated 
and somewhat compressed, like the metacarpal bones, may be considered as presenting a dorsal, a plantar, and two lateral sur- 
faces. The dorsal surface of all is covered by the tendons of the extensor muscles, the extensor brevis digitorum, and the vessels 
and nerves ; that of the first is broad, inclined inwards, and bounded externally by a prominent line ; in the last it looks outwards, 
and is bounded on the inner side by a like line. In the others arc observed analogous lines, placed in the middle, and separating 
the attachments of the interossei muscles. The plantar surface corresponds to the deep-seated muscles of the foot, and to liga- 
ments serving to connect those bones. That of the first is broader than any of the others. The lateral surfaces form the interos- 
seous spaces, and give attachment to the interosseous muscles. The tarsal extremity presents, in the first, an oval concave surface, 
broader above than below, articulating with the first cuneiform bone, and inferiorly a tuberosity for the attachment of the peroneus 
longus; that of the second metatarsal bone, triangular in its form, is, in consequence of the shortness of the corresponding cunei- 
form bone, impacted between the two other bones of that name ; it gives attachment to ligaments, articulates behind with the 
second cuneiform bone, on the inner side with the first metatarsal bone, and on the outer with the second. The tarsal end of the 
third, also triangular, and smaller than the preceding, receives the insertion of ligaments on its upper and under surfaces, and 
articulates posteriorly with the third cuneiform bone, on the inner side with the second metatarsal bone, on the outer with the 
fourth. The extremity of the fourth metatarsal bone, cubical in its form, is connected by ligaments to the adjacent bones, and 
articulates with the cuboid posteriorly, on the inner side with the third metatarsal and third cuneiform bones, on the outer with 
the fifth metatarsal. The posterior extremity of the fifth metatarsal bone, pyramidal in its form, articulates behind, by an oblique 
surface, with the cuboid, and on the inner side with the fourth metatarsal bone ; on its external and lower side is a rough tuberosity, 
which forms a considerable projection on the external border of the foot, and gives attachment to the peroneus brevis, and to 
part of the abductor minimi digiti. 

The anterior extremities of the metatarsal bones are convex, and rounded into the form of heads, flattened at the sides and 
elongated from above downwards. The head is bounded by a groove, or neck, better marked on the upper than on the under 
surface. These extremities are received into shallow depressions in the first phalanges, with which they are articulated. 

Phalanges of the Toes. — The toes, which form the last part of the foot, are composed each of three phalanges or rows, 
except the first, which has but two. The body of the first presents three surfaces: one inferior, or plantar, is fiat ; the others, 
lateral, are smooth and convex, and meet on the dorsum in a rounded border; they are contracted towards the middle, somewhat 
rough and broad at the extremities for the attachment of ligaments; concave towards the sole of the foot, and convex superiorly. 
The posterior extremities, broader than the anterior, are concave, and receive the head of the metatarsal hones. The anterior 



70 

i l I— Ai with an intervening pulley-like surface, the lateral parts being received into depressions, in the 
„. riIim ate m two rounded heads, with an mterve ^f P"' / ve lod a promine nt line marked on the latter. 

KnnlM , extremities of the second phalanges, wh 1st the m dd te groo g £ ^ g ^ ^^ ^ 

The bones of the M «,„rf^W, much smaUer ^f^^J^^ are terminated by two small concave articular 
tlR , UI) ,, r on e ; their borders are flat and compressed. The poste o exU em Y ^ _ 

Rur&cea senarated bv a prominent line, by which means they are adapiea 10 uie iiuy e 

o 1, f lllanges. The anterior extremities present two small condyles, which articulate with he third phalanges 

The th.rcl set are somewhat conical in their figure; the posterior extremities, or base, being hollow for their articulations 
with the ends of the second phalanges, whilst the anterior is rough and scabrous. 

\lttachments ofmuscL-Tolte metatarsal bones. The first gives attachment to the prolonged tendon of the peroneus 
lomrua to the transversal* pedis, and the first dorsal interosseous muscle; the second, to the first and second dorsal interossei ; the 
third 'to part of the adductor pollicis, to three interossei, and part of the transversalis pedis ; the fourth, to three interossei also ; 
the fifth, to the peroneus brevis and tertius, the transversalis pedis, part of the flexor brevis minimi digiti, to the fourth dorsal and 
third plantar interosseous muscle. . 

To the bones of the toes. The first phalanx of the great toe gives insertion to the abductor, flexor brevis, and adductor 
pollicis- the second phalanx, to the extensor proprius pollicis and flexor pollicis longus; the secoiid phalanges of the other toes 
receive the insertion of the tendons of the flexor sublimis; and the third, those of the flexor profundus and of the extensors. 

Ossa Sesumoidea.— These do not properly form part of the skeleton ; they may be considered as accessories to the tendons 
of muscles, and are found only in the limbs, never in the trunk. In the superior extremity, two are always found in the articula- 
tion of the' metacarpal bone of the thumb with its first phalanx. In the lower extremity, two are frequently found behind the 
femoral condyles, and constantly beneath the first joint of the great toe, as well as in the tendons of the tibialis posticus and 
peroneus longus. They are situated in the direction of flexion, (the only exception being the patella, which belongs to this class 
of bones,) and serve the purpose of increasing the power of muscles, by removing them farther from the axis of the bone on which 
they are intended to act. 

LIGAMENTOUS SYSTEM. 

Articulations. — The different pieces of the osseous system being connected together so as to form a skeleton, their modes 
of union must be as various as their forms and use's. When the union is not immediate, as in the case in the cranial bones, it is 
effected I >y means of different substances, such as ligament, cartilage, fibro-cartilage, and fibrous membrane, variously arranged 
and disposed, so as to permit, in some instances, no perceptible motion ; whilst in others a free and extended range is allowed in 
every direction. Still, all the varieties, however numerous, are usually included under the general term "articulation." 

The articulations are divided into three classes, viz. the immovable, the movable, and mixed ; the last being intermediate in 
degree between the others. The first form obtains where flat and broad bones are united to enclose cavities for the lodgment of 
important organs, as in the cranium and pelvis. In some instances the surfaces are indented and reciprocally impacted one into 
the other, so that complete solidity is insured by the structure of the part ; and as this mode of union occurs only amongst flat 
bones, their deficiency in extent of contact is compensated by the indentations in their margins. There is another set of immovable 
articulations, in which the surfaces are merely in apposition with one another, yet total immobility is secured by what may be 
termed a mechanical contrivance. Thus, though the squamous part of the temporal bone merely rests against the inferior border 
o\ the parietal, no motion can exist between them, in consequence of the manner in which the petrous portion of the former bone 
projects into the base of the skull. 

All the bones of the head and face, except the lower jaw, are joined by immovable articulation, or synarthrosis, (aw, together; 
afOpoi, articulation.) of which there are several forms. 

1. The first is called suture, (sutura, a seam.) In the true suture the union is effected by indentations in the contiguous 
margins of bones which are mutually received into one another, as may be seen between the two parietal, the occipital, and frontal 
bones ; any varieties that occur being referable to the form of the prominences. Thus, when they are tooth-shaped, the suture is 
termed sutura dentata; if like the teeth of a saw, sutura serrata; if the adjacent borders be bevelled off, as where the temporal 
and parietal bones are applied to one another, it is called a squamous suture, [sutura squamosa.) In some parts it may be 
observed that the mode oi union and adaptation are alternated, in order to increase their power of resistance. Thus, at the 
superior part of the arch ot the skull, the frontal overlies the parietal bones, and rests on them ; but inferiorly and laterally the 
reverse takes place, where the parietal rests against the frontal. 

When the surfaces are merely placed in apposition with one another, as in the superior maxillary bones, the union is called 
hartnanui. (op«, to adapt.) J ' 



When a ridge in one bone is received into a °toovp in annther the „,.*;„ i .• • u i ,.,,., 
-: . „,, - . , . ""nun s roo^e in another, the articulation is called schindylesis, U x <.vhv>, n ^u 

figure.) The rostrum of the spheno.d, and the descending plate of the ethmoid bone, are joined in this way with' tL . 

, > rm r/7 "T1 Ta '" ^ the tei ' m S ° mph0SiS ^ a ™ il ) ls ad °P<ed, which may be exemplified by 

the manner in which the teeth are lodged in the alveoli. ivy j i i 



a slit or 
the vomer. 



71 

In the mixed form of articulation, or amphi-arthrosis, the bones are connected by an intermediate substance, which allows 
some degree of motion. The articulations between the bodies of the vertebrae, the union of the pubic symphysis, and that 
between the two first bones of the sternum, are all constructed on this principle. As the surfaces in these cases are flat and plain, 
they possess in themselves no mechanical advantage ; so that their union is maintained partly by the cartilages interposed between 
them, and partly by ligamentous and fibrous structures disposed round the articulations. 

In the movable articulations, or diarthrosis, (Sta, through; apOpov, articulation,) as the surfaces are merely in contact with 
one another, the connexion between the parts is maintained by means of ligaments and fibrous membranes ; for, though cartilages 
are interposed between their adjacent extremities, they do not form a bond of union between them ; on the contrary, they are 
calculated to facilitate motion, rather than to restrain it. But the muscles which surround the different movable articulations con- 
tribute materially to retain the articular surfaces in their natural situations, and to prevent displacement. This is particularly 
evident in the shoulder-joint, in which the head of the humerus is kept in contact with the glenoid cavity of the scapula not so much 
by the fibrous capsule, which is weak and loose, as by the surrounding muscles ; for if these be weakened by paralysis, luxation 
may be readily produced. The joints in the extremities are all referable to the movable class; so is that of the lower jaw with 
the skull, and of the latter with the vertebral column. In the greater number of instances one of the articular surfaces is convex, 
the other concave ; but each of these forms exhibits some varieties of conformation, which are marked by particular names. 
Thus, an articulating surface, which is rounded and globular, so as to represent a segment of a sphere, is called a head; but, if it 
be elongated, the term condyle is used. These are in some cases supported by a contracted or thin portion, (neck,) which con- 
nects them with the body of the bone. If two condyles be placed in apposition, so as to leave a fossa between them, and 
constitute a pulley-like surface, it is termed trochlea. When plain even surfaces articulate, it is not necessary to mark them by 
any particular name ; in describing them they are referred to generally as articulating surfaces. Some of the articulating depres- 
sions have also received names taken from certain peculiarities in their conformation. Thus, the superior extremity of the ulna, 
which receives the trochlea of the humerus, is called the sigmoid cavity, from some resemblance to the Greek letter 2, (aty^a, ufos, 
like;) others are denominated from their greater or less degree of depth or shallowness. The deep cup-shaped cavity which 
receives the head of the femur is called cotyloid, (from xotv^r;, a cup, and ft3o;, like;) and the shallow oval depression to which the 
head of the humerus is applied, receives the name of glenoid cavity, (from y^wn, a shallow cavity, and "Soj, like.) 

The varieties of diarthrosis are : — 1. Enarthrosis, (tv, in; apOpov, a joint,) which in common language is called the " ball-and- 
socket" joint ; such as we see in the hip and shoulder. In these great freedom of motion is provided for. — 2. Jirthrodia, which 
comprises joints with a limited motion, as in the case of the carpal and tarsal bones, which merely slide for a little way upon each 
other. The articulations between the tubercles of the ribs and the transverse processes of the vertebrae, and those between the 
articular processes of the last-named bones, also come under this head. 

As the extent and form of the articulating surfaces of joints, as well as their ligamentous connexions, vary in different 
instances, so must their degrees of solidity and mobility: and, on a review of the whole of the articulations, it may be laid down 
as a general principle, that the greater their mobility, the less their solidity ; or, in other words, that the one is inversely as the 
other. All the motions, however, which are admissible in joints may be arranged under four heads, viz. motions of gliding, 
angular movement or opposition, circumduction, and rotation. 

1st. The contiguous surfaces of every movable articulation admit a certain degree of gliding motion upon one another ^o 
that it may be regarded as common to all ; but in some cases it is the only one which takes place, for instance, between the 
different bones of the carpus and tarsus. We thus observe that some joints admit of all the motions here indicated ; some are 
deprived of rotation, retaining the rest; whilst in others nothing more than a mere gliding can take place between the surfaces ;. 
so that a regular gradation is established in their degrees of mobility between the most movable and those which are least so. 
The shoulder-joint admits of the greatest extent and variety of movement ; those between the carpal and tarsal bones are exceed- 
ingly limited in these particulars ; and finally, between the latter and those which are altogether immovable, an intermediate 
grade may be traced, of which the pubic symphysis presents an example. 

2d. The angular movement, or opposition, can only take place between long bones. If these be made to move in opposite 
directions, as from extension to flexion, or from abduction to adduction, they form with one another angles varying in degree 
according to the extent of the motion. This, in some cases, as in the elbow and knee, is confined to flexion and extension, which 
makes them strictly ginglymoid or hinge-joints, (yiyyXv/*oj, a hinge;) in others the motion is general, and extends to four opposite 
directions, including each of the points intermediate between them, as may be observed in the shoulder, in the hip, and the meta- 
carpal joint of the thumb, all which joints admit of a circumduction in the part to which they belong. 

3d. The motion of circumduction is performed when the shaft of a bone is made to describe a cone, its summit corresponding 
with the superior articulation, the base being at the inferior extremity of the bone. While this motion is being executed, the 
limb passes successively through the states of elevation, abduction, depression, adduction, and of course through all the inter- 
mediate points ; and if a pencil be held between the fingers, and its point applied to any plain surface, such as a wall, it will trace 
a circle corresponding with the base of a cone, whose summit is at the shoulder-joint, whilst its side coincides with the line described 
by the out-stretched limb as it traverses the different points just enumerated. 



72 

ill, notation differs altogether from circumduction. In the latter the bone suffers a change of place as it moves from one 
point to another; in the former, it merely turns on its own axis, and therefore retains the same relative situation with respect to 
the adjacenl parts This movement, however, admits of two varieties; in one, it is performed on a pivot, as m the motion of the 
n the vertebra dentate ; in the other there is a sort of compound motion, for instance, where the radius rolls on its own axis 
at one end, whilst at the other it moves upon the extremity of the ulna, by which its lower part describes a segment of a circle, 
and therefore changes place nA certain extent. The femur and humerus also admit of a rotatory motion; in the latter, as the 
heed is closely applied upon the shaft, the axis of motion nearly coincides with that of the bone ; but in the former, in consequence 
of the length of the neck, and of the angle which it forms with the bone, the rotation is performed round an imaginary axis, which 
ui.i y be conceived to pass from the globular head to the condyles. 

There are but two articulations in which all the motions of opposition, circumduction, and rotation can be performed, namely, 
the hip and the shoulder joint. In these a convex surface is applied to one which is concave, the former being hemispherical, 
which is essentially necessary to such a freedom of motion. As joints constructed on this principle are more liable to displace- 
ment than any others, their security is in a great measure provided for by their being placed at the superior extremity of the limb, 
by which they are withdrawn from the influence of external forces. This arrangement is made subservient, not to the security 
of the joints solely, but also to a very important purpose in the functions of the limb ; for, as these free and extended motions are 
performed in the superior articulation, their effect is communicated to the whole limb, so as to compensate for the more restricted 
movements in the lower joints. 

Though all the motions above mentioned take place in the hip and shoulder joints, each of them, considered singly, is not 
performed with equal facility in both. Thus, circumduction is executed with greater ease in the shoulder than in the hip. 
Rotation, on the contrary, is more free and perfect in the latter than in the former. Circumduction can be executed with ease 
only when the axis of motion coincides (or very nearly so) with that of the lever to be moved, as is the case in the humerus; but, 
in the femur, the length of the neck of the bone removes the axis of motion considerably from that of the shaft, and thereby 
impedes circumduction in proportion as it facilitates the rotation of the limb. These differences of structure in the superior joints 
of the two extremities bear a direct relation to the conformation of their other articulations, and to the purposes for which they 
are adapted. For, as the inferior extremity is intended to sustain the weight of the body and for progression, the bones of the 
leg must be securely fixed, which could be effected only by diminishing their mobility; on this account no rotation or supination 
is allowed between the tibia and fibula; but, to compensate for this deficiency, rotation is permitted in the hip. But as the superior 
extremity, on the contrary, is fitted for the prehension of objects, and for quick and varied movements, free motion is allowed 
between the hones of the fore-arm, and between the latter and the carpus, in order that the hand and fingers may be more readily 
directed and applied to such objects as are required to be seized for different purposes ; and the power of pronation and supination, 
thus conferred, more than compensates for any deficiency in the rotatory motion of the humerus. 

It has been already observed, that rotatory motion in a bone presupposes the existence of a globular head, placed so that its 
axis shall form an angle with the shaft. Wherever this requisite is wanted, motion is confined to opposition and circumduction, 
as occurs in the articulation of the thumb with the carpus, in the phalanges with the metacarpal bones, and in the clavicle with 
the sternum. In these joints, the articulating surfaces are placed at the ends of the more movable bones ; and, as their axes 
coincide with that of motion, rotation is prevented; but circumduction and opposition are freely performed. When these are 
limited m extent, as in the sternoclavicular articulation, it arises rather from the accessory ligaments of the part than from any 
impediment in the surface of the bones; and if motion in one direction be more free than in another, as in the digital phalanges 
• with the metacarpus, where flexion and extension are more free than abduction and adduction, it proceeds partly from the 
existence of the lateral ligaments, and partly from the great power possessed by the flexor and extensor muscles compared with 
tho.c which perform the other movements. Though in the knee and elbow the axis of motion coincides with that of the bones, 
yel their movement is confined to two directions, viz. to flexion and extension. In these joints all other motions besides those 
just mentioned are prevented by the breadth of the articulating surfaces, and by their mode of adaptation : however, when they 
are flexed, some degree of lateral motion, and also of circumduction, can be performed ; as any individual may ascertain by resting 
his elbow on a table, when he will find that the fore-arm may be made to describe a cone with its summit at the olecranon and 
base towards the fingers. 

The structures entering into the composition of the articulations, are ligaments, fibro-cartilage, cartilage, elastic fibrous tissue, 
and synovial membrane. 

Ligament* (ligamenta ; »*. .to bind) form the chief means by which the numerous pieces of the osseous system are bound 
oge her so as to constitute one whole-the skeleton. Their form and size must vary considerably in different parts, some being 

Hat bands, some rounded cords, and others short but wide tubes attacherl m ww n ^ ( u u- u i ■ c r 

. , ,. mueb, auacnea at both ends to bones which admit of free movement 

upon one another, as we see in the capsular ligaments of the hin and thp AnnM« v ■ r 4 .. 

.livi.i*. ti, a , , . *u e i % ,., p shoulder. Viewing ligaments in this way, we may 

diMde them into two groups, the funicular or cord-like, and the capsular- th^r „™ i » j j? • , .- , • 

nnci.mn ;„ „i„n , .». • ♦• . . ' capsular, they are also called, from a mere consideration ot their 

position in relation to their respective joints, anterior and nnstprmr ;r,t Q ™~i j A ' 

formation nf Joint. „„ i M »i Lf V , dmenor i ana P oste nor, internal and external, lateral. Most ligaments enter into the 
tormation ot loints, and are therefore articular; some, however merelv fill .^or,o„ .u , ,- • , r 

, me, uuwever, merely nu up spaces, as the interosseous ligaments in the fore-arm 



73 

and leg ; or connect parts between which no motion exists, at the same time that they diminish vacuities, of which the sacro 
sciatic, and the two proper ligaments of the scapula, furnish examples. The term "false ligaments" is frequently applied to 
certain folds of serous and synovial membranes, from their being supposed to confine the parts to which they are attached. The 
broad processes of peritonaeum extended from the bladder and uterus to the sides of the pelvis, also the so-called ligamentum 
mucosum in the knee-joint, may be cited as instances : the expression is obviously ill-chosen, and should be discontinued. 

Fibro-cartiluge, as the name implies, is a structure intermediate between fibrous tissue and cartilage, and partakes of the 
qualities of both, viz. firmness and elasticity. Being calculated to serve different purposes in the economy, it presents not a few 
varieties both of appearance and structure. Thus, we find it in the form of broad thin plates in the pieces of the larynx and 
epiglottis, in the pinna of the ear, in the lateral and median cartilages of the nose, and in the tarsal cartilages of the eye-lids ; for 
in these parts it forms their basis of support, and determines their form ; whilst in the trachea it consists of narrow plates curved 
round the tube, forming a series of rings. In the immovable articulations, fibro-cartilage is interposed between the contiguous 
surfaces of bones, in layers of various forms and thickness, constituting in some instances the principal means of connecting them 
together, as we see at the junction of the ossa pubis, and also of the bodies of the vertebrae, in which instances the elastic property 
is of considerable utility. In some of the movable articulations, pieces of this structure are also placed, their form and size 
necessarily varying in each instance. In the knee-joint, — in the articulation of the lower jaw-bone, and in that of the clavicle 
with the sternum, they diminish the effects of jarring motions by their elasticity, and by a certain degree of mobility, which allows 
them to give way as the bones move upon them, they keep up a perfect adaptation between the parts, notwithstanding the many 
inequalities of their surfaces. In the hip and shoulder joints they are so disposed as to deepen the articulating cavities, and lessen 
the liability to dislocation. 

Cartilage (cartilago, tissu cartilagineux^ zoxfipoj) is much more dense and solid than any of the preceding textures ; it is highly 
elastic, and by its resiliency resumes its original position when any compressing force, to which it may be exposed, is removed. 
Its colour is in general a silvery white, and not unfrequently presents that of mother-of-pearl ; its density is such, that all trace of 
its cellular nature, or of its being a modification of cellular tissue, is lost. Mr. Hatchett considers its chemical composition to be 
albumen, and a small quantity of phosphate of lime. It contains a considerable quantity of water, consequently soon dries on 
exposure to the air, becomes yellow, semi-transparent, and looses its elasticity; it resists maceration, and the action of cold water, 
for a long time, but is soon acted on by acids, or by boiling water, and converted into a gelatinous pulp. 

Cartilage serves as an adjunct to bone, or a substitute for it. In early infancy the different pieces of the skeleton are cartila- 
ginous ; but, in the progress of growth, bone becomes deposited in their places, and gradually supplants them altogether ; such 
cartilages are termed temporary. The articulating extremities of bones are covered with layers of cartilage, not merely to 
smoothen them, but also, by their elasticity, to lessen the effects of concussion. The thickness of these layers varies from half a line, 
or even less, to two lines ; it will generally be found greatest along the margins of concave surfaces, and towards the centre of those 
which are convex. The free surface of each articular cartilage is covered by the synovial membrane of the joint, from which it 
is impossible to separate it : the attached surface is in equally intimate union with the bone on which it rests.* 

* There are two subjects of some importance in the general anatomy of the joints, about which there is much difference of opinion, 1. As to whether the 
synovial membrane of the joints lines the free surfaces of the articular cartilages, or is arrested at their margin after leaving the fibrous capsule of the joint. 
2. Whether the articular cartilages are penetrated by blood-vessels, so minute as to escape detection in their healthy state, and yet be capable of conveying the 
liquor sanguinis, or colourless portion of the blood, or whether they are wholly non-vascular, and receive the innutrative fluids by imbibition through the cells of 
which they are composed from the blood-vessels in their immediate vicinity. The negative side of the question on both of these points, has found, latterly, many 
earnest supporters among anatomists and operating surgeons. An amputation of the knee-joint, which I performed during the last winter before the class of the 
Jefferson Medical College, at the Philadelphia Hospital, gave me an opportunity of observing the changes produced by morbid causes in the articular carti- 
lages, which would seem to favour the same negative view of the subject. From the diseased condition of the integuments of the leg, there was a scantiness 
of flap for covering the stump, which left the condyles of the femur partly exposed to view. From round the margin of the cartilage and the place of attachment 
of the crucial ligaments, in front of which the synovial membrane passes, there was, in the course of a fortnight, inflammation, secretion, and a rapid growth of 
vigorous granulations. On the surface of the cartilage of the condyles there was not the slightest trace of inflammation or secretion. The cartilage remained 
for many days unchanged, having its natural polished aspect, and totally insensible to the contact of an instrument. It then lost its polish, became soft and 
pulpy, like a joint exposed to maceration in a dissecting room, and separated flake after flake, till the compact layer of bone covering the cells of the 
epiphysis below was exposed to view. This was at first dark-coloured, on the separation of the last layers of the cartilage, but it soon became red and sensi- 
tive to the touch; small, firm, whitish conical elevations appeared over its surface, which grew into strong and healthy granulations, to which the margins of the 
flaps at the end of six weeks were firmly connected, leaving the patient a solid and serviceable stump. The patient suffered none of the constitutional irritation 
common to synovial inflammation, and it would be difficult to believe from the progress of this case, and analogous ones reported by Velpeau and others, 
either that the synovial membrane is spread over the cartilages of joints, or that the cartilages are themselves vascular. 

At an early period of fcetal life, the synovial membrane, with a layer of vessels below it, as asserted by Mr. Toynbee, (Memoir on the Non-vascular 
Tissues, Philos. Trans. 1811,) is spread over the articular cartilages. Towards the period of birth the sub-synovial vessels gradually recede from the sur- 
face of the articular cartilage, and form a zone around its margin. There are several minutely injected preparations in the College Museum, taken from young 
subjects, showing this zone of vessels, of which the general plan of arrangement is as follows — an arterial ramuscule of considerable size, is found concentric 
with the outer margin of the cartilage, below the synovial membrane, and just where the latter rises up to be lost on the side of the cartilage. From this 
ramuscule, branches are given off and secondary loops formed, somewhat like the arrangement of the mesenteric arches, forming on the side of the 
epiphysis an irregular network of vessels. The terminal branches are exceedingly minute radiated vessels, which mount up and are lost on the sides 
Boxes. — 10 



74 

The costal cartilages form so many elastic prolongations of the ribs, serving not merely to complete the arch from the spine 
to the sternum, but also, by means of their elasticity, to restore the ribs to their original position, after having been elevated by 
the effort <>f inspiration. 

Elastic fibrous tissue (tissu jaune elastique— tissu fibreux jaune ,— ligamenta flava— subflava) consists of pale yellow fibres 
placed parallel, whether their general direction is perpendicular or oblique, no decussation or crossing being observed between them ; 
they arc easily separable from one another, as but little cellular tissue connects them. As its name implies, elasticity is the chief pro- 
perty of this structure wherever it occurs, being developed to such a degree as to render it well calculated to form suspensory liga- 
ments, or to invest parts which are subject to considerable alternations of distension and contraction. Thus, in quadrupeds a strong 
band of clastic tissue (ligamentum nucha) extends from the spinous processes of the neck, and from some of those of the back, to the 
skull, the weight of which it supports without producing that sense of fatigue which would necessarily arise were muscle the sus- 
taining power. The corresponding structure in man is reduced to a rudimentary state, the balanced position of the head on the 
spinal column rendering any further provision unnecessary. The same material enters into the composition of the ligaments 
which connect the arches of the vertebra?, (ligamenta subflava.) 

Synovial membrane, (membrana synovialis, tissu synovial.) — Under this head are included the lining membranes of all the 
articulations in the body, together with a great number of secreting sacs, (bursas mucosas,) which occur in various parts, more 
particularly in those which are subject to motion and pressure. The secretion poured out by both is quite the same, though the 
names given to them would imply a difference ; and the purposes which they serve in the economy are also the same, viz., that 
of facilitating motion, and preventing the injurious effects of friction, by means of the fluid which they secrete. Synovial mem- 
branes, like those of the serous class, are shut sacs, without perforation or interruption of their continuity. 

Each articular synovial membrane lines the fibrous structures which connect the component parts of the joint, and is 
reflected over the smooth extremities of the bones. If a tendon passes across a joint, as that of the biceps muscle does in the 
shoulder, or if a ligament lies within it, as we see in the hip-joint, it is enclosed within a tubular sheath derived from the synovial 
membrane. Membranous processes and prolongations are found in some joints,"attached by one extremity, the other being loose 
and floating. They consist of duplicatures of the synovial membrane enclosing some adipose tissue, together with delicate vessels. 
These were at one time called "glands of Havers," after an anatomist of that name, who supposed them to be of a glandular 
structure, and to secrete synovia ; but this fluid is now known to be produced from the whole surface, and not by any particular 
glands or follicles. As to the properties of the tissue under consideration, we find it to be, wherever it is situated, soft, thin, pale, 
and semi-transparent, admitting of distension by the effusion of fluid, as in hydrops articuli, and capable of a slow contraction 
when absorption takes place. It possesses little or no sensibility in its natural condition, but produces severe suffering when 
attacked by acute inflammation. 

Articulations of the Spine.— The different pieces of the vertebral column are connected together by ligaments, by fibro- 
cartilage, and in some parts by synovial membranes ; the former serving to retain them in their situation, the latter to facilitate 
motion between the different bones. The bodies are joined by two ligamentous bands, extending the whole length of the chain, 
and also by the intervertebral substances. 

1. The anterior common ligament (plate VII. figs. 1, 7; ligamentum commune anterius, Soemmering; fascia longitudinalis 
anterior. Weitbrecht) is a strong band of fibres which is placed on the front of the bodies of the vertebrae, and reaches from the 
axis to the first bone of the sacrum, becoming broader as it descends. It consists of longitudinal fibres, which are dense firm, and 
well-marked. The superficial fibres extend from a given vertebra to the fourth or fifth below it; the set subjacent to these passes 
from the body of one to about the third beneath it ; whilst the deeper ones pass only from one vertebra to that next it The fibres 
are thicker towards the middle of the bodies of the vertebra than at their margins, or over the intervertebral cartilages ; by which 
means their transverse depressions are filled up, and the surface of the column rendered even. It may also be observed that they 
of the bevelled edges of the cartilages. They are reflected back from this point in the form of veins, according to Mr. Toynbee, but my observations have not 
rJZ^^r^ Us vascLri t y,isso altered in 

become the bone of the epiphysis, and that which is to rema'in as arL.ar ^ it ^Z "Jl^^r^STX^ 

but appear to send no vertical branches towards the free surface of the ,rti C ZV^Zt T 7 P ™"™™^ Oeely with the vessels of the epiphysis, 

is, however, more tough and periosteal in character than that on he ^ X of h c r i /T T^I ^^ imm ^^ °™^ them ' 

connecting the cart.lage and bone. It is well known that the articular cart lai n vouna K ^T ^ deSCribe<1 by "*' LiSt0 " 3S Cel ' U,ar tiSSU6 

and fr^i.e; whilst infold persons, the compact layer of the epiphysis IstlZ'tZlT^ " f '"* ^^^ *"»"**» "W* ™° W ^ 
bone below, as to be with difficulty removed from it by the ordinary process of cleamr" t7 , C j artlla g e jp coverin S k thin ' ri S id - and s ° »™ly ™ted to the 
fluids by imbibition from the epiphysal vessels and the marginal zone, some change is 1, LT ! ^ ^ *■* WhMe the Cartlla?e gPtS itS mtM ™ 

which the inner portions of the articular cartilages are gradually converted into bon Th \ ■ PaSS3Se ^ ' tS StruCture durin S lhe Progress of life, by 

some diseases of the joints blood-vessels and granulations may shoot up into the Ih fh " ^ heaUhy S<ate n0 Vesse,s can be in J e cted in cartilage, in 
I softened and removed after amputation at the knee-joint. It has been in ^ f w Cartlla . ge ' as in tlle instance mentioned above, where the carti- 
the cartilages has been observed ; that of Mr. Listen, detailed in a late „„ m k„, r am , deScn P tion most probably that the appearance of vascularity in 

number of the Medico-Chirurgical Transactions was from a diseased joint—!. P. 



75 

adhere more closely to the margins of the bones than to the middle of their bodies, and still more closely to the intervertebral 
cartilages. Upon the sides of the vertebrae there are some fibres which are thin and scattered, and reach from one bone to the 
other. 

2. The posterior common ligament (plate VII. fig. 3; ligamentum commune posterius, Soemm.; fascia longitudinalis pos- 
tica, Weit.) is situated within the spinal canal, and attached to the posterior surface of the bodies of the vertebra:, extending from 
the axis to the sacrum. It is smooth, shining, and broader opposite the intervertebral cartilages than opposite the bodies of the 
bones, so that its margins present a series of points or dentations with intervening concave spaces. In the greater part of its 
extent it adheres firmly to the fibro-cartilages and to the bodies of the vertebra?, and is separated by loose cellular tissue from the 
prolongation of the dura mater which lines the canal. 

3. The intervertebral substance (ligamenta inter-vertebralia, Weit.) is a plate or disc of fibro-cartilage, (plate VII. figs. 5, 
6,) placed between the bodies of each pair of vertebra?, from the axis to the base of the sacrum. They correspond in shape to the 
parts of the vertebra? between which they are interposed, and, like them, increase in thickness from the upper to the lower end 
of the column. The thickness of these plates is not, however, uniform in their entire circumference. As they contribute to the 
production and maintenance of the curves which naturally exist in the spine, they are thinnest anteriorly, in the dorsal region, 
where its concavity looks forwards, and, on the contrary, thicker in front, in the neck and loins, where the convexity of the column 
looks in that direction. They are covered anteriorly and posteriorly by the common ligaments, which are intimately adherent to 
them ; in the dorsal region they are connected laterally, by short ligaments, to the heads of all the ribs, which articulate with two 
vertebra?. The intervertebral substance is composed, towards its circumference, of thin plates of fibro-cartilage, resting on their 
edges, and placed one within the other, as it were concentrically. Thus the outer plate like a rim runs round the disc, its lower 
edge resting on the vertebra beneath it ; its anterior or convex surface being subjacent to the anterior common ligament, whilst its 
concave surface is in apposition with the plate next within it. They are not, however, so broad as that their upper edges may 
reach the vertebra above them, nor are they exactly perpendicular; they incline inwards a little, so as to allow other plates to be 
in a manner piled upon them : each cartilage being in fact composed of two or three tiers of very narrow plates thus disposed. 
The interstices between the plates are filled by a pulpy and apparently elastic substance ; and as the number of the plates gradu- 
ally decreases towards the centre, whilst the pulpy matter increases, the quantity of the latter is such, that, when the pressure 
which confines it is taken off by cutting through the intervertebral substance, it will rise up so as to assume a conical form. 

The articulating processes of the vertebra? are connected by irregular fibrous bands, (ligamenta processum obliquorum, 
Weit.,) forming a capsule outside the synovial membranes. These are longer and more loose in the cervical than in the dorsal or 
lumbar regions. 

The arches, or plates of the vertebra?, are connected by the ligamenta subflava, (plate VII. figs. 2, 4 ; ligamenta verte- 
brarum subflava, Weit.,) as their bodies are by the intervertebral cartilages. These consist of yellow elastic fibres, almost per- 
pendicular in their direction, as they pass from the inferior border of one arch to the adjacent border of that immediately below 
it. They extend from the root of the transverse processes at each side backwards to the point where the two arches converge at 
the origin of the spinous processes, where the margins of each lateral half of the ligament may be observed to be merely in 
contact. The superior border of the ligament is attached, not to the margin exactly of the arch, but rather higher up on its 
anterior surface ; whilst the inferior border is prolonged a little on the posterior surface, as well as the margin of its correspond- 
ing arch. They do not exist between the occiput and the atlas, or between the latter and the axis ; common fibrous membrane 
supplies their place in these two spaces. They are most distinctly seen when the pedicles and arches are detached from the 
bodies of the vertebra?, so that they may be viewed from within the theca vertebralis. At the posterior aspect of the spine they 
appear short, and, as it were, overlaid by the arches. 

The articulation of the Spinous processes (plate VII. figs. 2, 7) is effected by means of the supra-spinous and inter-spinous 
ligaments. 1. The supi-a-spinous ligament consists of small, compressed bundles of longitudinal fibres, which connect the sum- 
mits of the spinous processes, and form a continuous chain from the seventh cervical vertebra to the spine of the sacrum. The 
posterior fibres pass down from a given vertebra to the third or fourth below it; those more deeply seated.reach only from one 
to the next, or the second beneath it. 2. The inter-spinous ligaments, thin and rather membranous, extend from the root to 
near the summit of each spinous process, connecting the inferior border of one with the superior border of that next below it. 
They exist in the dorsal and lumbar regions only, and are intimately connected with the extensor muscles of the spine. The 
inter-transverse ligaments are found only between the transverse processes of the inferior dorsal vertebra?, and even there very 
indistinctly, for they are united so intimately with the sacro-lumbalis muscle, that their fibres arc quite confused. 

Articulations of the two upper Vertebrse. — The articulation of the axis with the atlas (plate VIII. figs. 1 — 6) is effected by 
means of their articulating processes, also (in the place of intervertebral substance, which would be altogether incompatible with 
the requisite movements) by the odontoid process of the former, which is connected in a particular manner with the arch of the 
latter, and constitutes the pivot on which the head turns in its rotatory motions. There are three ligaments and four synovial mem- 
branes in this articulation. 

The transverse ligament (ligamentum atlantis transversum, Weit. Soemm.) is a strong, thick fasciculus of fibres, compressed 



76 

from before backwards, arched in its direction, and attached on each side to the inner border of the superior articulating processes 
of the atlaa It is broader and th,cker at the middle than at its extremities. From the middle of its posterior surface a short 
thin bundle of fibres passes down to be attached to the root of the odontoid process, whilst another passes up to the basilar pro- 
These appendages form a cross with the transverse ligament, and serve to bind the occiput to the two first vertebra. ; from 
,!ns is derived the term cruciform, which is sometimes applied to the transverse ligament. To bring these structures into v.ew, 
the posterior part of the vertebral arches must be removed. 

The anterior Mlo-axoid ligament passes from the border of the anterior arch of the atlas, and its tubercle, to the body of 
the axis and the root of its odontoid process. It is thin and membranous. 

The posterior Mo-axoid ligament connects the posterior arch of the atlas with the plates of the axis. Thus the interstices 
between the plates or arches, which in all the other vertebrae are filled by the ligamenta subflava, are occupied by a loose mem- 
brane between the second and first, as well as between the latter and the occiput. The edges of the articulating processes are con- 
nected by irregular fibres passing from one to the other. 

Two synovial membranes are placed between the articulating processes of the atlas and axis. One between the odontoid 
process and the transverse ligament, another between it and the arch of the atlas. 

Articulations of the Cranium.-The cranium is articulated, 1, with the atlas ; 2, with the axis ; 3, with the lower jaw. 
The articulation of the cranium with the atlas (plates VIII. figs. 1-6) takes place between the condyles of the occipital 
bone and the superior articulating processes of that vertebra, which are connected by ligaments and synovial membranes; it is 
also connected with the same by the two following ligaments. 

The anterior Occipito-alloidean ligament (membrana annuli anterioris vertebr&s prima?) extends from the anterior border 
of the occipital foramen, between the condyles, to the margin of the arch of the atlas between its superior articulating processes. 
Tins is thin, broad, and membranous; but in the median line a sort of accessory ligament is placed in front of it, which is thick, 
round, and composed of vertical fibres, attached above to the surface of the basilar process, and below to the small tubercle on 
the front of the atlas. The anterior surface of these ligaments is covered by the recti antici muscles, the posterior covers the 
odontoid process and its ligaments. 

The posterior Occipito-alloidean ligament, also broad and membranous, is attached superiorly to all that part of the margin 
of the occipital foramen winch is behind the condyles, and inferiorly to the adjacent border of the posterior arch of the atlas. It 
consists of two lamella:, which are united at their superior attachment, but soon divide, one becoming blended with the dura 
mater, which lines the vertebral canal, whilst the other is inserted into the arch of the atlas. The posterior surface of the liga- 
ment is in apposition with the posterior recti and superior oblique muscles, the anterior looks towards the vertebral canal; at each 
side, mar the articular processes, the ligament forms part of the foramina through which the sub-occipital nerves and vertebral 
arteries pass. 

The articulation of the occipital bone with the axis is effected through the medium of ligaments, as no part of their surfaces 
comes into contact. 

The Odontoid ligaments (ligamenta alaria) are two thick bundles of fibres attached below to each side of the summit of the 
odontoid process, and passing up diverging to be implanted into the rough depressions at the inner side of the condyles of the 
occiput, and also to a small part of the margin of the occipital foramen. Their direction, therefore, is obliquely upwards and out- 
wards; the triangular interval which they thus leave is filled by some thin fibres passing almost perpendicularly from the margin 
of the foramen to the summit of the process. These are strictly check ligaments ; the middle set, last described, prevent what 
may be termed a retroversion of the head, whilst the lateral pair check its rotatory motions. 

The Occipilo-axoidean ligament seems to be a prolongation of the posterior common ligament ; it is attached above to the 
inner surface of the basilar groove, from which it descends perpendicularly, becoming narrow, and opposite the axis is blended 
with the posterior common ligament. It covers the odontoid process and its check ligaments, and is intimately connected with the 
transverse ligament. 

Articulation of the Lower Jaw. — The lower jaw articulates (plate VIII. figs. 7 — 11) at each side by one of its condyles 
with the glenoid cavity in the temporal bone; hence it is called the temporo-maxillary articulation. By means of an inter-arti- 
cular cartilage a double joint is formed at each side, with distinct synovial membranes. 

The External lateral ligament is a short fasciculus of fibres, attached above to the external surface of the zygoma, and 
to the tubercle at the bifurcation of its root; below, to the external surface and posterior border of the neck of the condyle, its 
fibres being directed downwards and backwards. Externally it is covered by the parotid gland, internally it is in relation with 
the inter-articular cartilage and synovial membranes. 

The internal lateral ligament, thin, loose, and elongated, extends from the spinous process of the sphenoid bone downwards, 
and a little forwards, to be attached to the inferior maxillary bone at the lower border of the dental foramen, where it is some- 
what expanded. Its external surface is in relation superiorly with the external pterygoid muscle, and in the rest of its extent 
with the ramus o( the jaw. from which it is separated by the internal maxillary artery and dental nerve. Its inner surface is 
concealed by the internal pterygoid muscle. 



77 

The Stylo-maxillary ligament, thin and aponeurotic, passes from near the point of the styloid process to the inferior border 
of the angle of the jaw, where it is inserted between the masseter and internal pterygoid muscles. 

The inter-articular fibro-cartilage is a thin plate, placed horizontally between the articular surfaces of the bones ; it is of 
an oval form, and somewhat thicker at its margins than at its centre, where it is sometimes perforated. Its inferior surface, which 
is in contact with the condyle, is concave ; the superior is alternately concave and convex when taken from before backwards, 
conforming in some way with the outline of the articular cavity. Its circumference is connected at the outside with the external 
lateral ligament, anteriorly with the external pterygoid muscle. • 

The synovial membrane, after lining the superior surface of the inter-articular cartilage, is reflected upwards on the external 
lateral ligament, and over the smooth part of the glenoid cavity ; a similar membrane is interposed between the inferior surface 
of the cartilage and the condyle, so as to constitute a double joint. 

Articulations of the Ribs. — The ligaments of the ribs (plate VII., figs. 1, 2, 7, 8, 9) may be divided into three sets: those 
which connect them — 1, with the bodies of the vertebrae ; 2, with their transverse processes; 3, with the sternum. 

The Costo-vertebral ligaments (lig. capitulorum costarum) consist: 1. Of an anterior ligament which connects the head of 
each rib with the sides of the bodies of the vertebrae ; its fibres, flat and radiated, are divided into three bundles, of which the 
middle one passes horizontally forwards upon the corresponding intervertebral cartilage, whilst the superior ascends to the body 
of the vertebra above it, and the inferior descends to that below. From the divergence of its fibres, this is usually called the 
Stellate ligament. 2dly. Of an inter-articular ligament, which is a thin and short band of fibres which passes transversely 
from the ridge separating the two articular surfaces on the head of the rib to the intervertebral substance, and dividing the articu- 
lation into two parts, each lined by a separate synovial membrane. This ligament does not exist in the articulation of the first, 
eleventh, or twelfth ribs, and in consequence there is in them but one synovial capsule. 

The Costo-transverse ligaments connect the tubercles of the ribs with the transverse processes of the vertebra; ; from their 
position they are named posterior, middle, and anterior. 1. The posterior costo-transverse ligament, (lig. transversum externum 
costarum, Weit.,) consists of a very short thick fasciculus of fibres which passes from the posterior surface of the summit of the 
transverse process to the rough unarticulated part of the tubercle of the rib. Those of the superior ribs ascend, those of the 
inferior descend somewhat. 2. The middle costo-transverse ligament consists of a series of very short parallel fibres, which 
unite the neck of the rib to the anterior surface of the contiguous transverse process. These fibres are seen by removing hori- 
zontally a portion of the rib and transverse process, and forcibly drawing one from the other. 3. The anterior costo-transverse 
ligament (lig. transversum internum costarum, Weit.) is usually divided into two fasciculi of fibres, both nearly in apposition, and 
on the same plane. They pass from the neck of the rib obliquely upwards and outwards to the lower margin of the transverse 
process next above it. These do not exist in the articulations of the first and last ribs. The articulations between the tubercles 
of the ribs and the transverse processes are provided with synovial capsules. 

The Costo-sternal articulations, (plate VII., figs. 10, 11,) situated between the anterior extremities of the cartilages of the 
ribs and the fossae, in the margins of the sternum, are covered and supported by, 1, an anterior set of ligamentous fibres, thin, 
scattered, and radiated, passing from the extremity of the cartilage to the anterior surface of the sternum, where they interlace 
with those of the opposite side, and are blended with the aponeurosis of the pectoralis major muscle ; 2, a posterior set of fibres 
similarly disposed, but not so thick or numerous, connecting the thoracic surfaces of the same parts ; 3, a synovial membrane, 
interposed between the ends of each true rib and the sternum, and also between the margins of each pair of false ribs, where they 
articulate with one another. These can be readily demonstrated by slicing off a little of the anterior surface of the sternum and 
cartilages. A thin fasciculus of fibres connects the cartilage of the seventh rib with the xiphoid cartilage, and is thence called the 
Coslo-xiphoid ligament. The pieces of the sternum are connected by a layer of fibro-cartilage placed between their contiguous 
borders ; and, on the anterior and posterior surfaces, some scattered ligamentous fibres may be observed running longitudinally, 
which serve to strengthen their connexion. These are sometimes called the anterior and posterior sternal ligaments. 

Articulations of the Superior Extremities. — These may be arranged under the following heads, taking them in their ana- 
tomical order, from above downwards : 1, the articulation between the sternum and clavicle ; 2, that of the scapula and hilmerus ; 
3, of the elbow ; 4, of the wrist ; 5, of the hand ; 6, of the fingers. 

The superior extremity has but one point of bony attachment to the trunk, namely, that at the sterno-clavicular articulation, 
the scapula being connected with the trunk by muscles only. The clavicle articulates with the first bone of the sternum, and is 
connected with its fellow of the opposite side, and the first rib, by ligaments. 

The Sterno-clavicular articulation (plate XVI., figs. 5, 6) consists of an anterior and posterior ligament, an inter-articular 
cartilage, and two synovial membranes. 

The anterior Sterno-clavicular ligament passes from the inner extremity of the clavicle, downwards and inwards, upon the 
surface of the sternum. It is broad, and consists of parallel fibres, and corresponds, internally, with the synovial membranes of 
the articulation, and with the inter-articular cartilage to which it is adherent ; externally, with the sternal origin of the sterno- 
mastoid muscle. 

The posterior Sterno-clavicular ligament, of similar conformation witli the last, lml nut so broad or strongly marked, is 



78 

placed between the same bones lying at the thoracic aspect of the joint. Its posterior surface is in relation with the sterno 
hvoideus and sterno-thyroideus muscles. . 

The inter*rticularfibro«artilage, nearly circular in its form, and thicker at its border than at the centre is interposed 
between the articulating surfaces of the sternum and clavicle. Towards its superior and posterior part it is attached to the mar- 
gin of the clavicle, and at the opposite point of the cartilage of the first rib. In the latter situation it is thin and somewhat 
prolonged, so that the inferior border of the clavicle rests upon it. - 

synovial membranes.-ln this articulation, as in that of the lower jaw, there are two synovial membranes, of which one is 
reflected over the sternal end of the clavicle and adjacent surface of the fibro-cartilage, the other is disposed similarly between the 
cartilage and the articulating surface of the sternum. 

The Inter-clavicular ligament is a dense fasciculus of fibres, placed transversely between the contiguous extremities of the 
clavicles. Its fibres do not pass directly across from one to the other ; they dip down, and are attached to the upper margin of 
the sternum, by which it is rendered concave from side to side. 

The Costoclavicular ligament (ligamentum rhomboides, Weit. Soemm.) does not properly form part of the articulation , 
yet it contributes materially to retain the clavicle in its situation.- It is attached inferiorly to the cartilage of the first rib near its 
sternal end, and passes obliquely backwards and upwards, to be fixed to a roughness at the under surface of the clavicle. 

The Scapuloclavicular arliculationivlzte XVI., figs. 7, S) is effected between the acromion process of the scapula and the 
external cud of the clavicle. These points are connected, 1st, by a superior ligament, which is a strong broad band of fibres, 
passing from the superior surface of the acromion to the adjacent extremity of the clavicle; 2dly, by an inferior ligament simi- 
lar to the preceding, and placed at the under surfaces of the same bones ; 3dly, by a synovial membrane lining the two articular 
surfaces of the bones. As there is an inter-articular cartilage, there are sometimes two narrow synovial sacs, disposed in the same 
way as those in the sterno-clavicular articulation. 

The Coraco-clavicular ligament, which connects the clavicle with the coracoid process of the scapula, presents two parts, 
each marked by a particular name. There is, however, no division between them, nor other distinction than that they look 
different ways. 

The posterior or internal fasciculus, (conoid ligament,) broad above, narrow below, is attached, inferiorly, to the root of the 
coracoid process; superiorly, to a rough space at the inferior surface of the clavicle, its fibres being directed backwards and up- 
wards. The anteriur or external fasciculus (trapezoid ligament) passes from the superior surface of the coracoid process upwards, 
to an oblique line extending outwards from the tuberosity into which the conoid ligament is inserted; with the latter it unites at 
an angle, one of its aspects being directed forwards and upwards, the other downwards and backwards. 

There arc two Ligaments (plate XVI. figs. 7, 8) proper to the scapula : 1. The Caracoid ligament (ligamentum proprium pos- 
terius) is a thin flat band of fibres, attached by its extremities to the opposite margins of the notch at the root of the caracoid 
process, which it thus converts into a foramen for the transmission of the supra-scapular nerve, the artery most commonly passing 
external to it. The Caraco-acromion ligament (ligamentum proprium antcrius) is a broad, firm, triangular fasciculus, attached 
by its broader extremity to the coracoid process, and by the narrower to the acromion, between which it is stretched almost 
horizontally. Its inferior surface looks downwards upon the shoulder-joint, the superior is covered by the deltoid muscle. 

The Shoulder-joint. — The globular head of the humerus and the glenoid cavity of the scapula are the osseous parts which 
compose this articulation, (scapulo-humcral.) As the head of the humerus is large and prominent, whilst the cavity is merely a 
superficial depression, it must be evident that they are retained in their situation not by any mechanical contrivance, but by the 
capsular ligament, and the muscles which are attached to the two tuberosities of the humerus. 

The Capsular ligament (plate XVI. figs. 7,8, 10) is attached superiorly round the margin of the glenoid cavity, and inferiorly 
round the neck of the humerus. It is broader in the latter than in the former situation ; and its laxity is such, that if the muscular 
connexions of the humerus be detached, this bone drops away from the glenoid cavity. The superior and inner part of this mem- 
brane is covered and strengthened by a bundle of fibres, passing outwards and forwards from the coracoid process to the great 
tuberosity ot the humerus, {cora co-humeral ligament.) Besides this, it receives additions from the tendons of the supra and infra 
spinatus muscles, from the teres minor and sub-scapularis, which are intimately connected with it, as they proceed to be attached 
to the tuberosities of the humerus. rims its superior part is thick and firm, the inferior comparatively thin and weak. Its 

internal surface is nned bv the synovial membrane: the external bpsirlp* tho ™„c.„i„o i a ■ i • i t, .u 

, , , . , .... . ' . . , , , ' CAi ei»di, oesiaes the muscles already mentioned, is covered by the 

deltoid; inferiorly, it is m relation with the long head of the tricens and th ™™„™fl i rJ, . ' . . „ . , , 

, . ° l me mce P s a "u the circumflex vessels. The insertion of its inferior border 

is interrupted to give passage to the long tendon of the biceps muscle. 

nnn/T uT"' fTT^ ^ ^ ^^ 1° ^ SfT" ^ *" tendon ° f the lo "§ head of the biceps muscle : this at its 

I d , „ .I ! inr Z! 1 n e "fir" TT f^ 01 " CaVhy ' "P^ 168 im ° tW ° Se ' S £*"* wbfcK, after encircling it, meet 

and unite interiorly. These fibres, by elevating the border of the cavity, render it a little deeper 

The synovial membrane lines the glenoid cavity, and is rpfWtPrl n^r ;.d . ., . , , 

U,c fibrous capsule, „„ which ,. is prolonged as far as , he „e k o t hTh Z ^'^ """' " reaC '' eS the """* S " rfaCC ° 

,po„ ,l,c ar.i'ular surface of U,e head ofiha, bone, gi g i, a loo, ™I I!! ™ 'T' TF", ^ *"■ ^'^ *"" " ? P ' 

, 5 «ing ii a smooth investment. Viewed in this way, it appears a simple shut 



79 

sac ; and such it would be but for the peculiar relation of the long tendon of the biceps muscle to the shoulder-joint. The tendon 
is in fact enclosed in a tubular sheath, formed by an offset or process of the synovial membrane, which is reflected upon it where 
it is about to pass through the fibrous capsule, and is thence continued up to the summit of the glenoid cavity, where it is con- 
tinuous with that part of the membrane which invests it. By this provision the integrity of the articulation and of the membrane 
is preserved. 

On the superior and external surface of the capsule a considerable bursa mucosa is situated, by means of which the contiguous 
surfaces of the coracoid and acromion processes, and of the coraco-acromion ligament, are rendered smooth and lubricated, to 
facilitate their movements on the subjacent capsule. 

The Coraco-humeral or accessory ligament, above noticed, extends obliquely over the upper and outer part of the articula- 
tion ; it is attached to the coracoid process, and thence descends, intimately connected with the capsule, to the greater tuberosity 
of the humerus. 

The Elbow-joint. — The lower extremity of the humerus is connected with the ulna and radius at the elbow, so as to form a 
hinge-joint. The sigmoid cavity of the ulna articulates with the trochlea of the humerus, so as to admit of flexion and extension 
only, while the cup-shaped depression on the head of the radius #an turn freely on the rounded tuberosity to which it is applied. 
The bones are connected by four ligaments and a synovial membrane. (Plate XXI. figs. 1 — 6.) 

The internal lateral ligament, composed of diverging and radiated fibres, presents two parts, each with a different aspect, 
one looking obliquely forwards, the other backwards. The anterior part is attached above, where it is narrow and pointed, to the 
front of the internal condyle of the humerus; its fibres, as they descend, become broad and expanded, and are inserted into the 
coronoid process, along the inner margin of the sigmoid cavity. The posterior part, of the same form, (triangular,) passes from 
the under and back part of the same process of bone downwards to the inner border of the olecranon ; the superior fibres of this 
portion extend transversely between the points just named, the rest become successively more and more oblique. 

The external lateral ligament, shorter and much narrower than the internal, is attached superiorly to the external condyle 
of the humerus, and inferiorly becomes blended with the annular ligament of the radius ; none of its fibres are prolonged to the 
surface of that bone, for if they were, they would check its rotatory motion. It is intimately connected with the tendinous attach- 
ment of the extensor muscles, on which account, when dissected, it presents a jagged, irregular appearance. 

The anterior ligament is a broad thin membrane, placed in front of the joint, extending from the rough margin of the fossa, 
which receives the coronoid process during flexion, downwards to the anterior border of the coronoid process, and to the annular 
ligament of the radius. Some of its fibres are directed obliquely downwards and outwards, others are vertical. 

The posterior ligament, loose and weak, consists of fibres proceeding in opposite directions ; thus some pass transversely 
between the adjacent margins of the fossa which receives the head of the olecranon ; whilst others, subjacent to these, but not very 
well marked, pass vertically from the superior concave margin of that fossa to the extremity of the olecranon. 

Though these structures are described and named as separate ligaments, it will be found, on examination, that they form a 
continuous membrane placed round the joint, as fibrous capsules usually are, except only that the irregularity of the surfaces to 
which they are attached prevents their continuity from being readily perceived, and gives them the appearance of distinct ligamen- 
tous connexions passing from one point of bone to another. 

The upper Radio-ulnar articulation. — The head of the radius articulates with the small sigmoid cavity of the ulna, on 
which it rolls when it is. made to turn on its axis. These surfaces are covered with cartilage, and invested by the synovial mem- 
brane of the elbow-joint. The radius is connected to the ulna by an annular ligament. 

The annular or orbicular ligament (plate XXI. figs. 2, 3, 4) is a strong band of circular fibres, which, by being attached to 
the borders of the small sigmoid cavity, forms a ring, encircling the head of the radius, and binding it firmly in its situation. Its 
external surface is in apposition with the external lateral ligament of the elbow, whose fibres are inserted into it ; the internal is 
smooth and lined by the synovial membrane. 

The synovial membrane of the elbow-joint, after having covered the articular extremity of the humerus, is prolonged a little 
on the anterior surface of that bone, as far as the attachment of the anterior ligament, where it is reflected, and applied to the 
internal surface of that membrane, lining it as far as its radio-cubital insertion ; at that point the synovial membrane leaves the 
fibrous one, and invests the articular surfaces of the radius and ulna, and is extended over them until it comes into apposition 
with the posterior ligament, by which it is guided to the extremity of the humerus ; in the same way, it lines the lateral ligaments. 
Besides these reflections, the membrane forms two pouches, one by being prolonged into the small sigmoid cavity, the other 
where it passes between the annular ligament and the contiguous surface of the head of the radius. 

When the joint is laid open, and the bones extended, it will be observed that the head of the radius is not in contact with the 
rounded articulating process of the humerus. On which account, in the extended state of the limb, the rotatory motions of this 
bone are performed with much less ease than in that of flexion, from its wanting support at its upper end. The part of the 
humerus here referred to is moreover covered with cartilage only on its anterior aspect, indicating that the radius moves on it only 
when in the flexed position. 

The middle Radio-ulnar articulation. — The interval between the radius and ulna in the fore-arm is filled up by an 



80 

interosseous ligament and a round ligament, which serve to connect them together, and form what is called the middle radio-ulnar 

^"^Lerosseous ligament (plate XXI. fig, 1,2; membrana interossea) is a thin, flat, fibrous membrane, the direction of its 
fibre* being obliquely downwards and inwards, from the inner sharp border of the radius to the contiguous one of the ulna. It 
Ls not reach the whole length of the bones, as it commences about an inch below the tubercle of the radius. The surfaces of 
this membrane are intimately connected with the deep-seated muscles of the fore-arm, serving to mcrease their pom s of origin as 
well as to connect the bones. Inferiorly, it leaves an opening for the transmission of the antenor interosseous vessels ; superiorly, 
there is another, but much larger interval, through which the posterior interosseous vessels pass. 

The round or oblique ligament (figs. 1, 6) in some measure supplies the deficiency left by the interosseous ligament at the 
superior part of the arm. It is a thin narrow fasciculus of fibres, extending obliquely from the coronoid process, downwards and 
outwards, to be attached to the radius, about half an inch below its tubercle. The direction of its fibres is therefore altogether 
difterent from that of the fibres of the interosseous ligament. 

The lower Radio-ulnar articulation.-At the lower or carpal ends of the radius and ulna, (plate XXI. figs. 1,2; plate XXII. 
12 4) the former rotates on the latter as. its point of supjtort, the articulating surface of the radius being concave, that 
of the ulna convex. The bones are connected anteriorly and posteriorly by some fibres passing between their extremities, so 
thin and scattered as scarcely to admit or require description, but internally they are joined by a fibro-cartilage and a synovial 

membrane. ... i r 

The fibro-cartilage, placed transversely between the bones, is attached by its base to a rough line separating the carpal from 
the ulnar articulating surface of the radius, and by its summit to a depression at the root of the styloid process of the ulna. Its 
superior surface looks towards the head of the ulna, the inferior to the cuneiform bone ; both are smooth, and lined by synovial 
membrane ; the inferior one by the large membrane of the wrist-joint, the superior by a small one peculiar to the radio-ulnar 
articulation. Its two borders are connected with the carpal ligaments. As the radius rolls on the ulna, this cartilage is carried 
with it, and forms its chief bond of union with the latter bone. 

The synovial membrane is frequently called membrane sacciformis, though there is nothing in its conformation which 
distinguishes it from other synovial sacs. It may be considered as presenting two parts, one projecting perpendicularly upwards 
into the articulation of the radius and ulna, lining the contiguous surfaces of each ; the other placed horizontally between the head 
of the ulna and the corresponding surface of the fibro-cartilage, lining them also ; both, however, are formed by a continuous 
membrane. 

The. Wrist-joint. — This articulation {radio-carpal) (plate XXI. figs. 7, 8; plate XXII. figs. 1, 2, 4) is formed above by the 
radius and triangular fibro-cartilage, and the first three bones of the carpus below. The articular aspect of the former, when 
viewed in the fresh state, presents an oval and slightly concave surface, its greatest breadth being from side to side. The surface 
of the radius is divided into two parts, by a line extending from before backwards; so that these, together with the cartilage, 
present three articular surfaces, one for each carpal bone. The scaphoid, semilunar, and cuneiform bones are articulated together, 
so as to form a rounded convex surface, which is received into the concavity above described. Four ligaments and a synovial 
membrane retain these parts in their situation, as follow : — 

The internal lateral ligament passes directly downwards, from the extremity of the styloid process of the ulna, to be attached 
to the cuneiform bone ; it also sends some fibres to the anterior annular ligament and the pisiform bone. Its form is that of a 
rounded cord ; its inner surface is in contact with the synovial membrane of the radio-carpal articulation. 

The external lateral ligament extends from the styloid process of the radius to a rough surface on the outer side of the 
scaphoid bone, some of the fibres being prolonged to the trapezium, and also to the annular ligament of the wrist. 

The anterior ligament, (radio-carpal,) broad and membranous, is attached to the rough border of the carpal extremity of 
the radius, and to the base of its styloid process, from which its fibres pass down to be inserted into the anterior surface of the 
scaphoid, semilunar, and cuneiform bones. It is pierced by several foramina for the transmission of vessels : one of its surfaces is 
lined by the synovial membrane of the joint, the other is in contact with the tendons of the flexor muscles. 

The posterior ligament extends obliquely downwards and inwards, from the extremity of the radius to the posterior surface 
of the semilunar and cuneiform bones ; its fibres appear to be prolonged for some way on the carpal bones. One surface is in 
contact with the synovial membrane, the other with the extensor tendons. 

The synovial membrane, after having lined the articular surface of the radius, and the triangular fibro-cartilage, is reflected 
on the anterior and posterior ligaments, and thence over the surface of the carpal bones. 

. Irticulation of the carpal bones.-The bones of the carpus consist of two sets, each united by its proper connexions, so as 
to lorm a row ; and the two rows are connected by fibrous bands and a synovial membrane, so as to form between them a joint. 
(Plate XXII. figs. 1, 2, 3.) The connexions proper to the first row are interosseous fibro-cartilages, and ligaments placed on their 
dorsal and palmar surfaces. 

The interosseous Jibro-cartilages are two lamellae, one placed at each side of the semilunar bone, connecting it with the 
scaphoid and cuneiform bones. The carpal extremity of these is smooth, and lined by the synovial membrane of the wrist-joint. 



81 

The palmar ligaments are two, one extending from the scaphoid bone to the semilunar, the other from the semilunar to the 
cuneiform, their direction being transverse, and as their fibres are partly united, they may be considered as a continuous band 
connecting these bones. 

The dorsal ligaments are also two, disposed similarly and connecting the same bones on their posterior surfaces. The pisi 
form bone stands out of the range, and rests on the palmar surface of the cuneiform, with which it is articulated by an irregular 
fibrous capsule and a synovial membrane. 

The carpal bones of the second range are also connected by similar means. Three dorsal and palmar ligaments pass 
transversely from one bone, to the other. There are, however, but two interosseous fibro-cartilages, placed one at each side 
of the os magnum, connecting it with the trapezoid externally, and the unciform internally. Such are the means of connexion 
peculiar to eacli row. 

The ligaments which connect the upper to the lower row of bones are placed at their palmar, dorsal, and lateral aspects. 

The lateral ligaments are placed one at the radial, the other at the ulnar border of the carpus ; the former connects the 
scaphoid bone with the trapezium, the latter the cuneiform with the unciform. 

The palmar or anterior ligament consists of short fibres, which pass obliquely from the bones of the first to those of the 
second range. The posterior is similar in structure and arrangement. 

Synovial membrane.— It may be observed, that the first range of carpal bones forms a concavity ; the second, particularly 
the os magnum and unciform, a convexity, which is received within it : by these means a ball-and-socket joint is formed, which 
is completed by a synovial membrane reflected over the articular surfaces of the different osseous pieces which compose it. The 
membrane, moreover, sends two processes between the three bones of the first row, and three between those of the second, so as 
to facilitate their respective motions. 

Carpo-metacarpal articulations.— -The last four metacarpal bones (plate XXII. figs. 1, 2, 3) are connected with those of the 
carpus by means of two sets of fibrous bands, situated, one on the palmar, the other on the dorsal surface, the latter being better 
marked. All but the fifth metacarpal bone receive two bands. Thus, to the second, or that of the fore-finger, a thin fasciculus 
of fibres passes from the trapezium, another from the trapezoid bone ; the third receives one from the latter, and also from the os 
magnum ; the fourth from the os magnum and also from the unciform ; but the fifth is connected to the latter only. On the 
palmar surface a similar mode of connexion exists, but the fibres are not so well defined. 

The carpal extremities of the last four metacarpal bones are bound together by three transverse fibrous bands on the palmar, 
and the same on the dorsal surface, passing from one to the other ; they are slight, and often ill-defined. 

The digital extremities of these metacarpal bones are connected at their palmar aspect by a flat band passing across them, 
and closely connected with the head of each ; this is called the transverse ligament. 

The metacarpal bone of the thumb is articulated on quite a different principle from the others ; for, as it admits of all the 
motions except rotation, it is connected to the trapezium by a capsular ligament, which passes from the rough border bounding 
its articular surface to the trapezium : these parts are lined by a synovial membrane. 

Articulation of the Phalanges with the Metacarpal bones. — The rounded head of each of the last four metacarpal bones 
being received into the slight concavity situated in the extremity of the first phalanx, is maintained in situ by two lateral 
ligaments, an anterior ligament, and a synovial membrane. (Plate XXII.) 

The lateral ligaments consist of dense fasciculi of fibres, attached by one extremity to the sides of the metacarpal bones, by 
the other to the contiguous extremity of the phalanges, the direction of the fibres being forwards and downwards. The anterior 
ligaments occupy the intervals between these on the palmar aspect of the joints; they are thin and membranous. The synovial 
membrane invests the surfaces of the heads of the bones, and is reflected on the ligaments which connect them. 

The phalanges are articulated with one another, on the same principle as that which obtains in the articulation between their 
bases and the metacarpal bones ; it is therefore unnecessary to repeat what has been just stated on that subject. 

There are some other fibrous and ligamentous structures which deserve to be noticed in this place, but not as being connected 
immediately with the joints ; they are rather accessories to the tendons of the muscles. Thus, along the margins of the phalanges, 
on their palmar aspect, are attached the vaginal ligaments, which form sheaths for the flexor tendons, and bind them securely 
in their situation ; these are thick and firm along the body of the phalanges, but over the flexures of the joints they are thin, so 
as not to impede their movements ; their inner surface is lined by a fine membrane resembling the synovial class, which is reflected 
over the tendons, giving to each a smooth and shining appearauce. 

The posterior annular ligament of the wrist is continuous with the fascia of the fore-arm, of which it may be considered 
a part. It extends from the extremity of the radius, at its outer border, to the inner border of the ulna and the pisiform bone, and 
serves to bind down the extensor tendons. 

The anterior annular ligament is a dense fasciculus of fibres, extended across the carpus from the pisiform and unciform 
bones to the trapezium and scaphoides, so as to form a canal which transmits the flexor tendons, retains them in their situation, 
and modifies their direction and power of action on the hand. 
Bones. — 11 



. Ir/icula/ions of the Pelvis.— The os sacrum, considered as the common point of support of the vertebral column above, the 
os coccygis below, and ossa innominata on each side, is connected with each of these in the following manner : — 

ro-vertebral articulation. (Plate XXV. figs. 1, 2, 4.)— The base of the sacrum is articulated with the last lumbar 
vertebra by means similar to those which connect the different pairs of vertebrae throughout the column; 1, by an inter-vertebral 
nee placed between their oval surfaces; 2, by the continuation of the anterior and posterior common ligaments; 3, a liga- 
mentum subflarnim connecting the arches of the last vertebra with the posterior border of the sacral canal ; 4, an inter-spinous 
ligament; 5, two synovial membranes between the articulating processes; and lastly, a sacro-vertebral ligament. All these, 
except the last, being similar to the connecting media throughout the column, require no farther description in this place. 

The Sacro-vertebral ligament extends obliquely from the transverse process of the last lumbar vertebra downwards to the 
depressed lateral surface at the base of the sacrum ; its form is triangular, as its fibres diverge and expand towards the sacro- 
iliac symphysis. 

The Ilio-lumbar ligament is extended horizontally between the summit of the transverse process of the last lumbar vertebra 
and the posterior extremity of the crista of the ilium, where its fibres expand somewhat, so as to give it a triangular form. This 
is t lie only bond of union between the true vertebrae and the os ilium. 

The Sacro-coccygean articulation (plate XXV. figs. 1, 2) is effected by, 1, an anterior ligament, consisting of irregular 
fibres, placed in front of these bones, subjacent to the rectum ; 2, by a posterior ligament more strongly marked, composed of 
fibres which descend upon the bones of the coccyx, from the margin of the inferior orifice of the sacral canal, which it serves to 
close in and complete ; 3, by a thin fibro-cartilage interposed between the contiguous extremities of the sacrum and coccyx with 
a synovial membrane which continues in the female to an advanced period of life. 

The several pieces of the coccyx are connected one to the other by a continuation of the anterior and posterior ligaments 
which unite the sacrum and coccyx, and by very thin interposed fibro-cartilages. In the adult male the union between the sacrum 
and coccyx, and that between the pieces of the latter, are usually ossific ; but in the female this change most commonly does not 
occur till a very advanced period of life, and the mobility increases during pregnancy. 

The Sacro-iliac articulation, (plate XXV. figs. 1, 2,) often named the sacro-iliac symphysis, or synchondrosis, is formed 
between the rough lateral surfaces of the sacrum and ilium closely applied to one another, and connected by an irregular lamella 
of a cartilaginous structure. In addition to these means of union, the pelvic bones are connected by the following ligaments: — 

The posterior Sacro-sciatic ligament, (plate XXV. figs. 1 — 4 ; ligam. sacro-ischiadicum majus, Weit., Scemm.,) elongated, 
broad, and triangular, is placed at the inferior and posterior part of the pelvis, whose lower aperture it assists materially in closing. 
Its base or broader part is attached to the postero-inferior spine of the ilium and to the side of the sacrum and coccyx; whilst its 
other extremity is fixed along the inner margin of the tuber ischii, where it expands somewhat, and sends upwards and forwards 
along the margin of the ramus of that bone a falciform process, which presents one surface looking towards the perinasal space, 
and the other resting on the internal obturator muscle and pudic artery. The posterior surface of this ligament gives origin to 
part of the gluteus maximus; the anterior is covered partly by the small sacro-sciatic ligament. 

The anterior or small Sacro-sciatic ligament (plate XXV. figs. 1—4; lig. sacro-ischiadicum minus, internum, Weit., 
Scemm.) is attached by its base to the side of the sacrum and coccyx, where its fibres are blended with those of the great liga- 
ment, and by its apex to the spinous process of the ischium; its form is triangular, the direction of its fibres forwards and out- 
wards. The spinous process of the ischium, its tuberosity, and these two ligaments, bound an oval interval, through which pass 
the obturator interims muscle, and the internal pudic vessels and nerve ; but above the border of the anterior ligament is a large 
oval opening, (bounded before and above by the margin of the ilium and ischium, and behind by the great ligament,) which trans- 
mits the pyramidalis muscle, the great sciatic nerve, the gluteal and ischiadic vessels and nerves. 

The posterior Sacro-iliac ligaments (plate XXV. fig. 2) consist of three or four sets of short irregular fibres, extended 
between the posterior rough portion of the surface on the side of the sacrum and the corresponding part of the ilium. Some of 
the fibres pass horizontally between the bones, others obliquely: of the latter, one band, extending downwards from the posterior 
superior spine of the ilium to the tubercles on the third or fourth piece of the sacrum, is described separately, under the name of 
(from its direction) the oblique, or (from being situated superficially to the others) the posterior sacro-iliac ligament. They are 
all placed deeply in the groove formed by the ilium and sacrum, and covered by the origin of the lumbar muscles. The anterior 
sacro-thac ligament consists of some thin irregular fibres, placed at the anterior aspect of the sacro-iliac symphysis, and attached 
to the pelvic surfaces of the sacrum and ilium. 

The Pubic articulation (symphysis pubis) (plate XXV. figs. 1, 4, 5, 6) is formed by the conjunction of the ossa pubis in the 
median line anteriorly Tins is effected by an elongated piece of fibro-cartilage, interposed between their surfaces, and connected 
to each. t consists of concentric lamellae, is thicker anteriorly than posteriorly, and frequently projects beyond the level of the 
bones in the latter direction. A provision is made in this part for a slight degree of movement, which, however, is more per- 
ceptible in the female than in the male. Each pubic bone, properly speaking, has its own plate of fibro-cartilage. These plates 
are connected by fibres passing transversely from one to the other at the fore part as well as at the upper and lower border; but 
at the nnddle and back part they are smooth, and often lined by a slight synovial membrane. The union between the bones is 



83 

strengthened, 1st, by an anterior pubic ligament, which consists of irregular fibres, passing obliquely across from one bone to 
the other, and decussating on the anterior surface of the fibro-cartilage ; the fibres are intermixed with those of the aponeuroses 
of the external oblique muscles of the abdomen; 2dly, the sub-pubic ligament, (ligamentum triangulare, arcuatum,) thick and 
triangular, which is placed beneath the symphysis, its sides being attached to the rami of the pubis, its base free and slightly con- 
cave, directed downwards and backwards to the perinseal space ; 3dly, by some indistinct fibres which are situated on the pos- 
terior surface of the articulation, and others placed on its upper border : these may be named from their position. 

The Obturator ligament (plate XXV. figs. 1, 4, 5; membrana obturans foraminis thyreceidis, Scemm.) is properly a fibrous 
membrane, inserted into the border of the obturator foramen, which it closes in its entire extent, except at the upper and outer part 
of its circumference, where a small oval aperture is left for the exit of the obturator vessels. The obturator muscles are attached 
to its surfaces. 

The Hip-joint. — This is a true ball-and-socket joint, in which the globular head of the femur is received into the acetabulum 
or cotyloid cavity. The articulating surfaces are covered by cartilage in the greater part of their extent. It is deficient, how- 
ever, at the bottom of the cavity, and also a little beneath the central point of the head of the femur ; the latter marking the in- 
sertion of the round ligament, the former a shallow fossa for the lodgment of the structure which has been called the synovial 
gland. The connecting means in this articulation are three ligaments, (plate XXV. figs. 1, 3, 7, 8,) viz. a capsular, cotyloid, and 
inter-articular ligament, together with a synovial membrane. 

The Capsular ligament, dense and firm in its texture, represents a fibrous tube, whose direction is downwards and out- 
wards ; being attached by one extremity round the margin of the cotyloid cavity, by the other to the neck of the femur. Its 
superior circumference, in the greater part of its extent, is attached to the bone, within two or three lines of the cotyloid ligament ; 
but opposite the notch, where the margin of the cavity is deficient, it is attached to the transverse ligament. Its inferior circum- 
ference is inserted in front into the oblique line leading from one trochanter to the other ; but superiorly and behind, its fibres are 
implanted into the neck of the bone, within a quarter of an inch of the trochanteric fossa, and about the same distance from the 
posterior inter-trochanteric line. The ligament is most dense and firm towards the superior and anterior part of the articulation ; 
inferiorly, its fibres are comparatively thin. A firm fasciculus of fibres extends obliquely downwards in front of the joint, inti- 
mately connected with the capsule, being calculated to strengthen it, hence it is called its "accessory" ligament; but as one ex- 
tremity of it is attached to the anterior inferior spinous process of the ilium, and the other to the anterior trochanteric line, it 
may be called the ilio-femoral ligament. 

The Cotyloid ligament is a fibro-cartilaginous ring, placed round the cavity, and serving the purpose of increasing its depth, 
and completing its border, where it is deficient. The broader part or base of this structure is attached to the bone, its thin edge 
is free, and both its surfaces are covered by the synovial membrane, the external being in contact with the capsular ligament, the 
internal with the head of the femur. Its fibres are not continued all round; they rather pass obliquely from without inwards, 
over the margin of the cavity, one extremity being attached to the outer, the other to its inner surface. At the cotyloid notch 
these fibres are continued from side to side, crossing one another, so as to render the circumference complete. Some additional fibres 
are superadded in this part; from Avhich circumstance, as well as its being stretched across from one margin of the notch to the 
other, it is usually named the tratisverse ligament. Subjacent to the transverse portion an interval is left for the admission of the 
articular vessels. 

The inter-articular ligament is not unfrequently called the " round" ligament, (ligamentum teres capitis femoris, Weit., 
Scemm.) It is a thick dense fasciculus of fibres, implanted by one extremity, which is round, into the fossa in the head of the 
femur ; by the other, where it is broad, flat, and bifid, into the margins of the cotyloid notch, where its fibres become blended 
with those of the transverse ligament. 

The synovial membrane lines the contiguous surfaces of all the parts which enter into the composition of the articulation, 
giving them a smooth and shining appearance. From the margin of the articular surface of the femur, it may be traced along 
the neck of that bone as far as the insertion of the capsular ligament, the inner surface of which it lines as far as its superior 
attachment. There it turns inwards over the cotyloid ligament, and dips into the cavity, lining its entire extent, and finally 
guided as it were by the inter-articular ligament, (which it invests by a funnel-shaped process,) it reaches the head of the femur, 
and invests it as far as the border of its cartilage, whence we proceeded in tracing its reflections. 

The Knee-joint. — This is a ginglymus, or hinge-joint, formed by the condyles of the femur above, the head of the tibia below, 
and the patella in front, the contiguous surfaces of each being tipped with cartilage, and invested by a common synovial membrane. 
The following ligaments (plate XXVII.) enter into the composition of the articulation: the ligamentum patellae, the external and in- 
ternal lateral, a posterior, a transverse, and two crucial ligaments ; besides these, may be enumerated two semilunar fibro-cartilages, 
and some folds of the synovial membrane, which have received names, viz., the ligamenta alaria and mucosum ; but the term 
ligament cannot with propriety be applied to any other than fibrous structures which connect parts tog< 

The ligament am Patellae is a flat strong band of tendinous fibres, which connects the patella with the anterior tuberosity of 
the tibia. Its superior extremity is attached to the apex of the patella, and to a depression on its posterior surface ; its superficial 
fibres pass upwards on the anterior aspect of the bone, and become continuous with those of the tendon of the rectus femoris; the 



84 

inferior extremity is a little expanded; towards the middle its borders are slightly tucked in. The anterior surface of this liga- 
ment is subcutaneous in its whole extent; the posterior rests on the synovial membrane of the knee-joint, from which it is sepa- 
rated by some adipose substance, as it is inferiorly from the head of the tibia by a synovial bursa. 

The internal lateral ligament, broad and flat, connects the tuberosity of the internal condyle of the femur with the inner 
surface of the head of the tibia. It becomes broad inferiorly, where it is covered by the tendons of the sartorius, gracilis, and 
semi-tendinosua muscles; internally it rests on the synovial membrane, and is attached to the internal semilunar cartilage. 

The external lateral ligament is a rounded cord-like fasciculus of fibres, which passes from the tuberosity of the external 
condyle of the femur, to the head of the fibula ; its direction is almost vertical ; it is placed nearer the posterior than the anterior 
surface of the joint ; its internal surface corresponds with the synovial membrane and the external articular arteries, the external 
being covered by the tendon of the biceps flexor cruris, and the expanded fascia of the extensor muscles. Posterior to this, but 
parallel with it, another ligament is placed, connecting the same points of the femur and fibula; it is called the short external 
lateral ligament. 

The posterior ligament, (ligamentum posticum Winslowi,) broad and expanded, is a flat plane of fibres, stretched obliquely 
behind the articulation, from the internal tuberosity of the tibia to the external condyle of the femur. The direction of the greater 
part of its fibres is from below upwards and outwards, running diagonally across the joint, being evidently continuous with the 
tendon of the scmi-membranosus muscle, of which they may be regarded as a prolongation. This ligament, however, cannot be 
considered as formed solely by a reflection of the tendon of the semi-membranosus, or merely as the third insertion of that muscle • 
for several transverse and perpendicular fibres are observed in it, distinct from those of the reflected tendon. Some apertures may 
be observed between its fibres, which transmit the posterior articular vessels. 

The crucial or oblique ligaments (ligamenta cruciata) are placed at the posterior part of the joint, external to the synovial 
membrane, but partially invested by it. As the name imports, their direction is oblique, so that they cross or decussate somewhat 
like the lines of the letter X ; the posterior one, however, approaches more nearly a perpendicular direction : of these one is ante- 
rior, the other posterior. The anterior ligament is fixed by its lower extremity to a pit, situated before the spine of the tibia, 
where it is connected with the anterior cornu of the internal semilunar cartilage ; its upper extremity is inserted into the inner side 
of the external condyle of the femur; hence its direction is upwards, backwards, and outwards. The posterior ligament is 
attached inferiorly to the pit behind the spine of the tibia, (where it is intimately connected with the posterior cornu of the external 
semilunar cartilage,) and superiorly, to the side of the inner condyle ; its fibres being directed upwards and a little forwards. Its 
interior surface is in contact with the last-mentioned ligament, and the posterior with the ligamentum posticum. Both arc thus 
implanted into the fossa between the condyles. 

The semilunar cartilages are two crescent-shaped lamella? of the fibro-cartilage, placed on the articulating surfaces of the 
head of the tibia, interposed between them and the condyles of the femur. The outer border of each is thick and convex, the 
inner thin and concave, leaving the central part of the superior surface of the tibia uncovered. 

The internal semilunar cartilage, elongated from before backwards, is nearly of a semicircular form ; its anterior cornu is 
connected with the anterior crucial ligament, and is inserted into the pit before the spine of the tibia ; the posterior is attached 
behind the spine, and is in relation with the posterior crucial ligament; its thick border is connected with the internal lateral liga- 
ment, the thin one is free and unattached. 

The external semilunar cartilage forms nearly a complete circle; its two cornua, fixed one before, the other behind the 
spine of the tibia, are so close at their insertion, that they may be said to be interposed between the insertions of the internal semi- 
lunar cartilage. Its external border is connected behind with the tendon of the popliteus muscle, and in the middle with the 
external lateral ligament. Towards the front of the joint the convex borders of the inter-articular cartilages are connected by a 
slight transverse band, (transverse ligament.) The superior surface of the fibro-cartilages is concave, and in apposition with the 
condyles of the femur; the mferior plane rests on the head of the tibia ; both surfaces are invested in nearly their entire extent by 
th" synovial membrane. 

The synovial membrane, like all similar structures, forms a shut sac, whose surface is continuous throughout its entire extent, 
and as ,t hues the cont.guous surfaces of all the parts entering into the composition of the knee-joint, it must necessarilv present 
rather a complex arrangement. This complexity is increased by the existence of a small funnel-shaped fold, (improperly named 
ligamentum mucosum,) winch .s stretched across the joint from the lower border of the patella to the margin of the fossa, between 
the condyles of the femur. In order to exhibit the arrangement of the membrane, the joint should be laid open by a vertical inci- 
sion earned along the inner margin of the patella and its ligament, leaving the ligamentum mucosum untouched. A lateral view 
ot the joint being thus obtained, all the parts remaining in their natural position, it will be observed that the synovial sac is inter- 
sected and in a manner div.ded into two parts by a transverse funnel-shaped process, {ligamentum mucosum;) the superior one 
elongated and pyramidal projects by Us summit more than an inch above the patella, its base corresponding with the breadth of 
tno process just named. The interior division of the membrane is mi.-wlriht r.,i • i \ ■ ■. ^ . c 

,, , . . - .. , ue 1S quadrilateral, one side being made up of the lower border of 

tli' 1 same proct ss. and the smooth surface of the femur with which it is rnntiimniio .,. ,1 i_ Zi • , • ,. ,. . 

which ii is continuous; another by the articulating surface of the tibia; 



85 

posteriorly it corresponds with the posterior crucial ligament, and anteriorly with the part of the membrane reflected on the 
ligamentum patellas. 

If we commence at the superior border of the patella to trace the reflections of the membrane, we find that it descends, lining 
its articulating surface; below its inferior border it corresponds with the ligamentum patella?, from which it is separated by a con- 
siderable quantity of adipose matter ; on reaching the margin of the tibia, it is reflected over its articulating surfaces, and also on 
both aspects of the semilunar cartilages, giving them a smooth investment ; round the crucial ligaments also it forms partial 
investments, enclosing them as far as their attachments to the femur. The membrane will thus be found to be guided to the 
articulating surface of that bone at several points, viz., by the two crucial ligaments, by the funnel-shaped process, and by the 
external margin of the semilunar cartilages ; from these points it expands over the condyles, and after ascending for some way in 
front of the femur, (forming a cul-de-sac between it and the tendon of the extensor muscles,) it passes downwards to the margin 
of the patella, from which we proceeded to trace its reflections. At the sides of the patella the membrane forms two slight folds 
which are named "alar" ligaments, (ligamenta alaria.) 

In the enumeration of the ligaments of the knee-joint, no mention has been here made of a fibrous capsule, as an invest- 
ment distinct from the other fibrous structures of the joint. If is not usually described in anatomical demonstrations, and no 
notice of it occurs in the works of Meckel, Portal, Cloquet, or B. Cooper. A capsular ligament is, however, attributed to this 
articulation by Soemmering, Weitbrecht, and Fyfe. The capsular ligament or membrane (membrana capsularis articuli genu) 
is said to arise in front from the whole circumference of the articulating extremity of the femur, at some distance from its cartila- 
ginous coating, and behind from the border of the inter-condyloid fossa, from which it descends, to be inserted into the rough 
border which surrounds the head of the tibia. The membrane is also inserted into the margins of the patella and its superior 
and inferior ligamentous connexions, so that this bone forms part of the capsule of the joint. "It is very thin, but is strengthened 
by the fascia of the limb, and the surrounding aponeurotic structures." 

These are pretty nearly the words employed by Fyfe ; the last clause approaches somewhat to a correct expression of the 
fact. The fascia lata is prolonged from the lower part of the thigh to the head of the tibia, and extends backwards upon the 
condyles, and forwards to the margins of the patella and its ligament ; thus forming an exterior investment for the joint and its 
synovial membrane. The ligamentum posticum supplies its place at the back of the articulation. 

Peronco-tibial articulation. — The superior andinferior extremities of the tibia and fibula are connected by ligaments and 
synovial membranes, (plates XXVI. XXVII.,) and the shafts of these bones are moreover maintained in relation by an interos- 
seous ligament. 

The contiguous extremities of the bones present superiorly two flat oval surfaces covered with cartilage, which are closely 
applied to one another, and retained in situ, 1, by an anterior ligament, which is a broad flat band of fibres, passing obliquely 
upwards and inwards, from the head of the fibula to the internal tuberosity of the tibia; it is covered and strengthened by the 
tendon of the biceps flexor curis; 2, by a posterior ligament, similarly disposed behind the articulation, but stronger and thicker; 
3, by a synovial membrane, which lines the articulating surfaces of the bones and ligaments. 

The interosseous ligament, (plate XXVI. fig. 6,) which connects the bodies of the tibia and fibula, flat and membranous, is 
composed of a series of parallel fibres, extending obliquely between the external ridge of the tibia, and the ridge on the adjacent 
surface of the fibula. Most of the fibres run outwards and downwards, others cross them, and the membrane they compose is 
broader above than below, and presents in the former situation an elongated opening for the transmission of the anterior tibial 
vessels, and inferiorly a smaller aperture for the passage of the anterior branch of the fibular artery. 

The inferior extremities of the tibia and fibula present two articulating surfaces, of which that of the former is concave, and 
receives the latter, which is convex, both being for a little way covered with cartilage ; these are connected by four ligaments and 
a synovial membrane. 

1. The anterior ligament (tibio-fibular) is a flat band of fibres, extended obliquely between the heads of the bones, the 
direction of its fibres being downwards from the tibia to the fibula. 

2. The posterior ligament, somewhat triangular, is similarly disposed behind the articulation ; its external surface is covered 
by the peronei muscles. 

3. The transverse ligament, longer but narrower than the former, with which its fibres arc closely connected, extends from 
the head of the fibula to that of the tibia ; it forms the posterior boundary of the ankle-joint. 

}. The inferior interosseous ligament consists of some short dense fibres, which connect the heads of the bones, as the 
great interosseous ligament does their bodies; it cannot be seen until the anterior and posterior ligaments are removed, and the 
bones in some degree separated. 

The Jinkle-joint. — This articulation (plate XXIX. figs. 9 — 13) consists of the inferior extremities of the tibia and fibula, 
united so as to form an arch, into which the superior convex surface of the astragalus is received. Their contiguous surfaces are 
covered with cartilage, lined by a synovial membrane, and retained in contact by the following ligaments. The internal lateral 
ligament (ligamentum deltoides) is a broad flat fasciculus of fibres, one extremity of which is attached to the inferior border of 



the internal malleolus, the other to the inner side of the astragalus and os calcis. It is broader below than above ; its cutaneous 
surface is covered bv the tendon of the tibialis posticus muscle ; the articular one is lined by the synovial membrane. 

The external lateral ligament consists of three distinct fasciculi of fibres, separated by intervals and disposed in different 
directions. 1. The central one {ligamentum fibulx medium) descends perpendicularly from the extremity of the fibula, and is 
inserted into the middle of the external surface of the os calcis. 2. The anterior fasciculus {ligamentum fibulx anterius) passes 
obliquely forwards from the inferior extremity of the fibula, to the anterior border of the articular surface of the astragalus ; it is 
the shortest of the three. 3. The posterior, {ligamentum fibulx posterius,) the strongest of the three ligaments, passes obliquely 
backwards from the extremity of the fibula, towards the posterior surface of the astragalus, where it is inserted into the border 
of the groove for the tendon of the flexor longus pollicis. 

At the anterior aspect of the joint is a broad thin membraneous band, composed of irregular fibres, extended obliquely from 
the border of the articulating surface of the tibia to the margin of the pulley-like surface of the astragalus. This is usually 
called the Tibio-tarsal ligament ; it is covered by the tendons of the extensor muscies. 

The synovial membrane, after having invested the articulating surface of the astragalus, is reflected upwards at each side 
upon the lateral ligaments, and at the anterior and posterior part* of the joint, upon the corresponding fibrous structures, so as to 
reach the articulating surfaces of the tibia and fibula by several points at once. These it lines in their entire extent, and also 
sends upwards between the bones a process which reaches as far as the inferior interosseous ligament ; so that the inferior articu- 
lation between these bones may be said to form part of the ankle-joint, as both are lined by the same synovial membrane. 

Articulations of the Foot. — The foot is constructed on the principle of an arch, being concave inferiorly, where it rests on 
the ground, and convex superiorly, where it receives the weight of the body, transmitted to it by the bones of the leg. The 
posterior extremity, or heel, is narrow, thick, and rounded; the anterior, flat, thin, and expanded, being composed of the digital 
phalanges. The internal border, longer than the external, thick, and nearly straight, is composed of the inner border of the cal- 
caneum, the scaphoid, first cuneiform, and first metatarsal and digital bones of the great toe:" the external, shorter and thinner, 
consists of the calcaneum, the cuboid, the fifth metatarsal, and corresponding digital bones. 

The foot being divided into the tarsus, metatarsus, and" phalanges, its different parts are respectively bound together by 
ligaments, and all are united so as to form a whole. 

The seven bones of which the tarsus consists may be divided into two sets, the os calcis and astragalus forming the first, the 
scaphoid, cuboid, and three cuneiform bones, the second. 

•Articulation of the Astragalus with the Calcaneum. — The astragalus is connected to the calcaneum by three ligaments, 
(plate XXIX. fig. 13, plate XXX.,) the chief of which is situated between the bones, and unites them somewhat after the manner 
that bivalve shells are connected by their muscle. This is termed the interosseous ligament ; its breadth from side to side is 
more than an inch ; the fibres of which it is composed pass perpendicularly between the bones, one extremity being fixed to the 
groove between the articulating surfaces of the calcaneum, the other to a corresponding depression in the astragalus. The pos- 
terior ligament connects the posterior border of the astragalus with the upper surface of the calcaneum; its fibres are oblique, 
its length and breadth not more than three or four lines. The external ligament is a slight fasciculus which descends perpen- 
dicularly from the under surface of the astragalus to the external side of the calcaneum; its direction is parallel with the external 
lateral ligament of the ankle-joint. It may be farther observed, that as the astragalus is wedged in between the malleoli, and as 
the lateral ligaments pass downwards from these to the os calcis, they must contribute somewhat to retain the astragalus in its 
proper position witli regard to the latter bone. 

. Articulation of the Calcaneum with the Scaphoid bone.— This is effected by means of two ligaments, (plate XXX.,) their 
surfaces not being in contact. Of these ligaments, the inferior or plantar one, (ligamentum calcaneo-scaphoideum inferius, 
Meckel^ much the largest, passes forwards and inwards from the extremity of the calcaneum to the inferior surface of the scaphoid 
bone ; its fibres are flat and horizontal, and in contact inferiorly with the tendon of the tibialis posticus muscle; superiorly they 
form part of the fossa which receives the head of the astragalus. The external or dorsal ligament (lig. calcaneo-scaphoideum 
externum) forms the external boundary of the cavity just mentioned; its fibres, very short, are directed from behind forwards 
between the contiguous extremities of the bones. 

Articulation iof the Astragalus unth the Scaphoid bone.-Tbe astragalus forms with the scaphoid bone a ball-and-socket 
joint. Plate XXX.) The anterior articulating surface of the calcaneum, and the inferior calcaneo-scaphoid ligament, also may 
be said to enter into tins articulation, as all the parts here mentioned are lined by a common synovial membrane. On the dorsum 
of the foot the astragalus is retained in its situation by the ligamentum astragalo-scaphoideum, a broad band of fibres extending 
obliquely forwards from the anterior extremity of the astragalus to the superior surface of the scaphoid bone It is covered by 
the extensor tendons. The necessity for an inferior ligament between these bones is removed by the existence of the calcaneo- 
scaphoid ligament. The synodal membrane lines the concave surface of the scaphoid bone, the calcaneo-scaphoid ligament, and 
the elongated articulating surface oi the calcaneum; from these it is reflected to the under surface of the astragalus and its 
scaphoid ligament, and so to the bone of that name from which we began to trace it. 

Articulation of the Calcaneum with the Cuboid bone. — The connexion h t™ on „ .1 i i ■ i r 

me connexion between these bones is maintained by three hga- 



87 

ments (plate XXX.) and a synovial membrane. The superior calcaneo-cuboid ligament is a broad flat band of fibres which 
connects the anterior and superior surface of the calcaneum with the adjacent part of the cuboid bone. The inferior ligament 
consists of two distinct fasciculi of fibres, differing in form and attachments, of which one is superficial, the other deep-seated. 
The superficial one, called the long plantar ligament, (ligamentum longum plantae,) is the longest of the tarsal ligaments. Its 
fibres, attached posteriorly to the inferior surface of the calcaneum, pass horizontally forwards, and become intimately connected 
with the rough tuberosity on the under surface of the cuboid bone ; the greater number of them are continued forwards, and 
terminate at the base of the third and fourth metatarsal bones. The deep-seated calcaneo cuboid ligament lies close to the bones 
being separated from the former by some cellular tissue ; its breadth is considerable, its length scarcely an inch, one extremity 
being attached to the calcaneum before the long ligament, the other (somewhat expanded) to the under surface of the cuboid 
bone. A synovial membrane lines the contiguous surfaces of the two bones, and is necessarily reflected upon the articular aspects 
of the superior calcaneo-cuboid ligament and the deep-seated ligament just noticed. 

Articulations between the second set or range of Tarsal bones. — The second range of the tarsal bones, viz. the scaphoid, 
cuboid, and three cuneiform, are connected together in the following manner, so as to form separate articulations between each 
pair of them. (Plate XXX.) 

1. The scaphoid and cuboid bones, when in contact, which is not always the case, present two small articulating surfaces, at 
their edges covered with cartilage, and lined by a synovial membrane. They are connected by a dorsal ligament, composed of 
short thin fibres, extended obliquely between the two bones; and a plantar, situated in the sole of the foot, and composed of 
transverse fibres. 

2. The cuboid and the external cuneiform bones are connected by a dorsal ligament, which is a thin fasciculus of fibres 
extended between them, and a. plantar ligament, whose fibres are transverse. 

3. The scaphoid and the cuneiform bones are held together by dorsal and plantar ligaments. It will be recollected that the 
scaphoid bone articulates with the three cuneiform by the smooth faces on its anterior surface. The dorsal ligaments, three in 
number, pass from the superior surface of the scaphoid to the first, second, and third cuneiform bones, into which they are 
inserted. The plantar ligaments are similarly disposed on the under surface of the bones, but not so strongly marked. 

4. The three cuneiform bones are connected by two dorsal and two plantar ligaments extended transversely from side to 
side ; the internal one is broader and stronger than the other. The contiguous flat surfaces of the bones are lined by synovial 
membranes. 

Articulation of the Tarsus and Metatarsus. — The four anterior bones of the tarsus, viz. the three cuneiform and the cuboid, 
articulate with the metatarsus. (Plate XXX.) The first and third cuneiform bones project beyond the others ; so that the anterior 
extremity of the tarsus is very irregular. The first metatarsal bone articulates, with the internal cuneiform ; the second is wedged 
in between the first and third cuneiform ; the third metatarsal bone articulates with the extremity of the corresponding cuneiform, 
and the two last with the cuboid bone. The articular surfaces of the bones are lined by synovial membranes, and they are held 
in contact by dorsal and plantar ligaments. These are flat, thin bands of parallel fibres, which pass from behind forwards, 
connecting the contiguous extremities of the bones just mentioned. Thus the first metatarsal bone receives a broad thin band 
from the corresponding cuneiform bone ; the second receives three, which converge to its upper surface, one passing from each 
cuneiform bone ; the third has one from the third bone of that name ; and, finally, the two last are bound by a broad fasciculus 
to the cuboid bone. The plantar set is similarly disposed ; the first and second are more strongly marked than the corresponding 
ligaments on the dorsal surface. 

Articulations of the Metatarsal bones with one another. — The five elongated bones which form the metatarsal are con- 
nected by ligaments, (plate XXX.,) so as to form an integrant part of the foot. At their posterior or tarsal extremity, two sets of 
ligaments are situated, one on the dorsal, the other on the plantar surface. These consist of three short thin bands of fibres, 
which pass transversely across the contiguous extremities of the four last metatarsal bones; the plantar set is similarly disposed; 
but no such connexion exists between the first and second bones. At the anterior or digital extremity the five bones are connected 
by a transverse ligament, which is a flat thin band of fibres passing across from the extremity of one bone to the other ; it is 
situated on the plantar surface of the metatarsus. 

Articulations of the Metatarsal bones with the Digital phalanges. — The anterior extremities of the metatarsal bones are 
connected (plate XXX.) with those of the phalanges by two lateral ligaments, an inferior ligament, and a synovial membrane, 
similar in every respect to those of the hand. 

The articulations of the phalanges with one another are also constructed on the same principle as those of the superior 
extremity, hi each, the bones are held in contact by two lateral ligaments, and an anterior ligament which is thin and mem- 
branous ; the surfaces being lined by a synovial membrane. 



INDEX. 



Acetabulum, page 63. 

Acromion process of the scapula, page 53. 

Amphi-arthrosis, page 71. 

Analogy between cranial bones and vertebrae, page 43. 

Antrum of Highmore, pages 31, 42. (PI. XIII.) 

Apophysis, page 5. 

Arthrodia, page 71. 

Articulations, page 70. 

ankle, page 85. (PI. XXIX.) 
atlas and axis, of the, page 75. (PI. VIII.) 
carpal bones, of the, page 81. (PI. XXII.) 
costo-sternal, page 77. (PI. VII.) 
cranium, with the first vertebrae, of the, page 76. 
elbow-joint, of the, page 79. (PI. XXI.) 
foot, of the, page 86. (Pis. XXIX. XXX.) 
hand, of the, page 81. (PI. XXII.) 
hip-joint, page 83. (PI. XXV.) 
knee-joint, page 83. (PI. XXVII.) 
lower jaw, page 76. (PI. VIII.) 
pelvis, of the, page 82. (PI. XXV.) 
peroneotibial, page 85. (Pis. XXVI. XXVII.) 
radio-ulnar, page 79. (Pi. XXI.) 
ribs, of the, page 77. (PI. VII.) 
scapuloclavicular, page 78. (PI. XVI.) 
shoulder-joint, of the, page 78. (PI. XVI.) 
sterno-clavicular, page 77. (PI. XVI.) 
vertebrae, of the, page 75. (PI. VII.) 
wrist-joint, page 80. (Pis. XXI. XXII.) 

Asternal ribs, see False ribs. 

Astragalus, page 68. (Pis. XXVIII. XXIX.) 

Atlas, page 13. (Pis. IV. V.) 

Axis, page 13. (Pis. IV. V.) 

Base of the skull, page 37. (PI. IX.) 
Bone, general anatomy of, page 3. 

structure of, page 5. 
Burste muscosan, page 74. 

Calcaneum, page 68. (Pis. XXVIII. XXIX.) 
Bones — 12 



Camper's facial angle, page 47. 

Canals of Havers, page 6. 

Carpus, page 58. (PI. XX.) 

Cartilage, page 73. 

Cells of Purkinje, page 6. 

Clavicle, page 55. (Pis. XVI. XVII.) 

Clinoid processes, page 26. 

Coccyx, page 61. (Pis. IV. VI. XIV.) 

Columna vertebralis, see Vertebral column. 

Coracoid process, see Scapula. 

Coronoid process, see Ulna. 

Costal cartilages, page 53. (PI. XIV.) 

Cribriform lamella, page 28. 

Crista galli, page 28. 

Cuboid bone, page 68. (Pis. XXVIII. XXIX.) 

Cuneiform bone, of the carpus, page 59. (PI. XX.) 

Cuneiform bones, of the tarsus, page 69. (Pis. XXVIII. XXIX.) 

Diarthrosis, page 71. 
Diploe, page 6. 

Elastic fibrous tissue, page 74. 

Enarthrosis, page 71. 

Ensiform cartilage, page 51. (PI. XIV.) 

Epiphysis, page 5. 

Ethmoid bone, page 27. (Pis. IX. X. XII.) 

Facial, angle of Camper, page 47. 
False ribs, page 51. 
Femur, page 65. (PI. XXIV.) 
Fibro-cartilage, page 73. 
Fibro-cartilages — 

of the coccyx, page 82. 

of the jaw, page 76. (PI. VIII.) 

of the knee, page 83. (PI. XXVII.) 

of the scapuloclavicular articulation, page 78. 

of the sterno-clavicular articulation, page 77. (PI. XVI.) 

of the wrist, page 80. (PI. XXII.) 
Fibrous tissue, elastic, page 71. 
Fibula, page 67. (PI. XXVI.) 

89 



90 



Foramen magnum, page 15. 

Frontal sinuses, pages 19, 12. (PI. IX. ) 

Frontal bone, page 18. (Pis. IX. XI.) 

Ginglymos, page 71. 
Glands of Havers, page 74. 
(iuinphosis, page 70. 

Eland, bones of the, page 58. (PI. XX.) 

Harmonia, page 70. 

Haversian canals, page 6. 

Humerus, page 55. (Pis. XVII. XVIII,) 

Inferior maxillary bone, page 33. (Pis. IX. XIII.) 
Innominatum, os, page 61. (Pis. XIV. XV. XXIII.) 
Ischium, page 63. (PI. XXIII.) 

Jugular fossa, page 25. 

Lachrymal bones, page 31. (Pis. IX. XII.) 
Ligamentous system — 

general considerations, page 70. 
ligaments, general anatomy of, page 72. 
acromio-clavicular, page 78. (PI. XVI.) 
alar, of the axis, page 76. (PI. VIII.) 

of the knee, page 85. (PI. XXVII.) 
ankle, of the, page 85. (PI. XXIX.) 
annular, of the radius, page 79. (PI. XXI.) 
wrist, anterior, page 81. 
posterior, page 81. 
arcuatum pubis, see subpubic. 

astragalo-calcanean, page 86. (Pis. XXIX. XXX.) 
astragalo-scaphoid, page 86. (PI. XXX.) 
atlantis transversum, page 75. (PI. VIII.) 
atlo-axoid, page 76. (PI. VIII.) 
breve planus, page 87. (PI. XXX.) 
oalcaneo-astrag-aloid, page 86. (Pis. XXIX. XXX.) 
cuboid, page 86. (PI. XXX.) 
scaphoid, page 86. (PL XXX.) 
eapitulorum costarum, page 77. (PI. VII.) 
capsular, of the hip, page 83. (PI. XXV.) 
knee, page 85. 

shoulder, page 78. (PI. XVI.) 
thumb, page 81. (PI. XXII.) 
carpal, page 8(0; (PI. XXII.) 
carpo-metacarpa], page 81. (PI. XXII.) 
common anterior, page 71. (PI. VII.) 
posterior, page 75. (PI. VII.) 
conoid, page 78. (PL XVI.) 
coracoid, page 78. (PL XVI.) 
coraco-acromial, page 78. (PL XVI.) 
clavicular, page 78. (PL XVI.) 
humeral, page 79. (PL XVI.) 
costoclavicular, page 78. (PL XVI.) 
sternal, page 77. (PL VII.) 
transverse, page 77. (PL VII.) 

tebral, page 77. (PI. VII.) 
xiphoid, page 77. (PL VII.) 



Ligamentous svstem — 

cotyloid, page 83. (PL XXV.) 
crucial, page 84. (PL XXVII.) 
cruciata, see crucial, 
cruciform, page 76. (PL VIII.) 
deltoid, page 85. (PL XXIX.) 
elbow, of the, page 79. (PL XXI.) 
fibula, of the, page 86. (PL XXIX.) 
glenoid, page 78. (PL XVI.) 
hip-joint, of the, page 83. (PI. XXV.) 
ilic-femoral, page 82. (PL XXV.) 
ilio-lumbar, page 82. (PL XXV.) 
inter-articular, of the hip ; see teres. 

of the ribs, page 77. (PL VII.) 
inter-clavicular, page 78. (PL XVI.) 
interosseous — 

calcaneo-astragaloid, page 86. (PL XXIX.) 
peroneotibial, page 85. (PL XXVI.) 
radio-ulnar, page 79. (Pis. XXI. XXII.) 
inter-spinous, page 75. (PL VII.) 
inter-transverse, page 75. (PL VII.) 
intervertebral, page 75. (PL VII.) 
knee, of the, page 83. (PL XXVII.) 
lateral, of the ankle, page 85. (PL XXIX.) 
elbow, page 79. (PL XXI.) 
jaw, page 76. (PL VIII.) 
knee, page 83. (PL XXVII.) 
phalanges, foot, page 87. (PL XXX.) 
phalanges, hand, page 81. (PL XXII.) 
wrist, page 80. (Pis. XXI. XXII.) 
longum plants, page 87. (PL XXX.) 
lumbo-iliac, see ilio-lumbar ligament, 
lumbo-sacral, see sacro-vertebral ligament, 
metacarpal, page 81. (PL XXII.) 
metacarpo-phalangeal, page 81. (PL XXII.) 
metatarso-phalangeal, page 87. (PL XXX.) 
mucosum, page 84. (PL XXVII.) 
oblique of the fore-arm, page 80. (PL XXI.) 
of the knee, page 84. (PL XXVII.) 
obturator, page 83. (PL XXV.) 
occipito-atloidean, page 76. (PL VIII.) 
occipito-axoid, page 76. (PL VIII.) 
odontoid, page 76. (PL VIII.) 
orbicular, page 79. (PL XXI.) 
patellae, page 83. (PL XXVII.) 
peroneotibial, page 85. (Pis. XXVI. XXVII.) 
phalanges of the foot, page 87. (PL XXX.) 
of the hand, page 81. (PL XXII.) 
plantar, long, page 87. (PL XXX.) 
short, page 87. (PL XXX.) 
posticum Winslowii, page 84. (PI. XXXVII.) 
processum obliquorum, page 75. 
proprium anterius scapula?, page 78. 

posticum scapulas, page 78. 
pubic, page 82. (PI. XXV.) 



91 



Ligamentous system — 

radio-carpal, page 80. (Pis. XXI. XXII.) 

radio-ulnar, page 79. (Pis. XXI. XXII.) 

rhomboid, page 78. (PI. XVI.) 

round, or oblique, page 80. (PI. XXI.) 

sacro-coccygean, page 82. (PI. XXV.) 

sacro-iliac, page 82. (PI. XXV.) 

sacro-ischiadicum, see sacro-seiatic. 

sacro- vertebral, page 82. (PI. XXV.) 

sacro-sciatic anterior, page 82. (PI. XXV.) 
posterior, page 82. (PI. XXV.) 

scapuloclavicular ligaments, page 78. (PI. XVI.) 

shoulder-joint, of the, page 78. (PI. XVI.) 

stellate, page 77. (PI. VII.) 

stemo-clavicular, page 77. (PI. XVI.) 

stylo-maxillary, page 77. (PI. VIII.) 

subflava, page 75. (PI. VII.) 

subpubic, page 83. (PI. XXV.) 

supra-spinous, page 75. (PI. VII.) 

tarsal, page 86. (PI. XXX.) 

tarso-metatarsal, page 87. (PI. XXX.) 

teres, page 83. (PI. XXV.) 

tibio-fibular, page 85. (Pis. XXVI. XXVII.) 

tibio-tarsal, page 86. 

transverse of the acetabulum, page 83. (PI. XXV.) 
atlas, page 75. (PI. VIII.) 
metacarpus, page 81. (PI. XXII.) 
metatarsus, page 87. (PI. XXX.) 
scapula, see coracoid ligament, 
semilunar cartilages, page 84. 

transversum internum costarum, page 77. 
externum costarum, page 77. 

trapezoid, page 78. (PI. XVI.) 

triangulare, page 83. (PI. XXV.) 

vaginal, of the phalanges, page 81. 

wrist, of the, page 80. (Pis. XXI. XXII.) 
Linea aspera, page 65. 

Magnum, os, page 59. (PI. XX.) 
Malar bones, page 31. (Pis. IX. XII.) 
Man, his adaptation to the erect posture, page 43. 
Mastoid process, page 23. 
Maxillary sinus, see Antrum of Highmore. 
Meatus auditorius, page 23. 

Membrana interossea, peronec-tibial, page 85. (PI. XXVI.) 
radio-ulnar, page 79. 
sacciformis, page 80. 
obturans foraminis thyreceidis, page 83. 
Metacarpus, page 59. (PI. XX.) 
Metatarsus, page 69. (PI. XXVIII.) 

Nasal bones, page 31. (Pis. IX. XII.) 

Nasal fossa;, page 4 1 . (PI. IX.) 

Navicular bone, page 68. (Pis. XXVIII. XXIX.) 

Obturator foramen, page 64. 

Occipital bone, page 15. (Pis. IX. X.) 



Olecranon, page 58. 

Orbits, page 41. (PI. IX.) 

Os calcis, page 68. (Pis. XXVIII. XXIX.) 

Os hyoides, page 35. (PI. XIII.) 

Os planum, page 28. 

Ossa triquetra or Wormiana, pages 17, 29. 

Osseous system, page 3. 

Ossification, process of, page 7. 

Os unguis, see Lachrymal bones. 

Palate bones, page 32. (Pis. IX. XII.) 
Parietal bones, page 17. (.Pis. IX. X.) 
Patella, page 66. (PI. XXIV.) 
Pelvis, page 60. (PI. XV.) 

general conformation of, page 64. 

measurements of the, page 65. 
Phalanges of the foot, page 69. (PI. XXVIII.) 

hand, page 60. (PI. XX.) 
Pisiform bone, page 59. (PI. XX.) 
Processus cochleariformis, page 25. 
Pterygoid processes, page 26. 
Pubic symphysis, page 82. 
Pubis, os, page 62. (PI. XXIII.) 
Punctum ossificationis, page 8. 
Purkinjean corpuscules, page 6. 
Pyramidal bone see Cuneiform bone. 

Radius, page 57. (Pis. XVII. XIX.) 
Ribs, page 51. (Pis. XIII. XIV. XV.) 

Sacro-iliac symphysis or synchondrosis, page 82. 

Sacrum, page 61. (Pis. IV. VI. XIV. XV.) 

Scaphoid bone, hand, page 58. (PI. XX.) 

Scaphoid bone, foot, page 68. (Pis. XXVIII. XXIX.) 

Scapula, page 54. (Pis. XVI. XVII.) 

Schindylesis, page 70. 

Semilunar bone, page 58. (PI. XX.) 

Sesamoid bones, page 70. (Pis. XX. XXVIII.) 

Skeleton, pages 3, 8. (Pis I. II. III.) 

Skull, page 15. (Pis. IX. X. XI.) 
conformation of the, page 37. 
Sphenoid bone, page 25. (Pis. IX. X. XII.) 
Sphenoidal sinuses, page 42. (PI. IX.) 
Sphenoidal spongy bones, page 25. 
Spheno-maxillary fossa, page 39. 
Spine, page 10. (PI. IV.) 
Spongy bones, see Turbinate bones. 
Sternum, page 49. (PI. XIV.) 
Superior maxillary bone, page 29. (Pis. IX. XIII.) 
Sutures, pages 35, 70. (PI. IX.) 
Symphysis pubis, page 82. (PI. XXV.) 

sacro-iliac, page 82. 
Synarthrosis, page 70. 
Synovia] membrane, page 74. 

Tarsus, page 68. 

Teeth, anatomy of, page 49. 



Temporal bones, page 20. (Pis. IX. X. XI.) 
Temporal fossa, page 30. (PI. IX.) 
Thorax, page 49. 
Tibia, page 6C. (PI. XXVI.) 
Trapezium, page 59. (PI. XX.) 
Trapezoid bone, page 59. (PI. XX.) 
Trochanter, major and minor, page 65. 
Tuber ischii, page 63. (PI. XXIII.) 
Turbinate bones, page 33. (Pis. IX. XII.) 

Ulna, page 57. (Pis. XVII. XIX.) 
Unciform bone, page 59. (PI. XX.) 



Vertebra dentata, see Axis. 
Vertebra prominens, page 13. (Pis. IV. V.) 
Vertebrae, page 11. (Pis. IV. V. VI.) 
Vertebral column, page 10. (PI. IV.) 
Vomer, page 33. (Pis. IX. XII.) 

Wormian bones, pages 17, 29. 

Xiphoid cartilage see Ensiform cartilage. 

Zygoma, page 22. 
Zygomatic fossa, page 39. 



END OF THE BONES AND LIGAMENTS. 



THE 



MUSCLES 



OF 



THE HUMAN BODY. 



THE MUSCLES 



OF 



THE HUMAN BODY. 



The muscles of the body are the agents by which its different efforts and movements are performed. In ordinary language 
they are known by the name flesh, and as such they differ considerably in colour and consistence in different classes of animals. 
A muscle is a compound structure made up of cellular tissue for its basis, which encloses in its areolae fibrine as the essential 
constituent. Tendinous fibres are superadded in most muscles, particularly at their extremities, forming the means of attachment 
to the periosteum and the bones. 

When we look at a muscle dissected, it evidently appears made up of fibres arranged in a defined direction ; several of 
these are observed to be aggregated into bundles, (fasciculi,) each of which is detached from the rest by a thin lamella of delicate 
cellular tissue. Each fasciculus admits again of being separated into fibres, and these into fibrillar ; and the separation may be 
continued until we at length arrive at some so minute as to be incapable of farther division ; these may be regarded, thereto re, 
as ultimate fibres, at least in reference to our methods of analysis. 

The muscles thus formed of bundles or groups of fibres, cither singly or in various combinations, draw upon the different 
parts of the skeleton to which they are attached, and put them in motion, or steady and fix them as circumstances may require. 
As the skeleton, or frame-work of the body, consists of more than two hundred separate pieces, the muscles which move them 
are proportionally numerous, being about two hundred and twenty pairs. The bones may be considered as so many passive 
insiruments, and the muscles as active agents; for they possess a peculiar property, by virtue of which their fibres contract and 
shorten themselves in obedience to the will, or on the application of some stimulant. Most muscles are under the direction of 
the will, which acts upon them through the brain and nerves. Others, however, as the heart, and the muscular coat of the 
stomach and bowels, are withdrawn from the control of the will, though still they are influenced by and through the nervous 
system. Hence it is that the former are termed voluntary, and the latter involuntary muscles, whilst those which are connected 
with the movements of respiration deserve the name of mixed muscles ; for though they are subject to our volition, it is only to 
a limited extent, and they continue their action when the will is suspended, as in sleep. 

The nomenclature of muscles is confessedly intricate and confused, owing, in a great measure, to its being the work of 
different individuals acting without concert, and adopting each a different basis for the construction of the terms employed, so 
that no scientific or general principle runs through it. Thus the names of some are taken from the mere circumstance of their 
occurring or appearing in a certain order — first, second, third — taken from a particular point of view. The earlier anatomists 
adopted this simple plan of naming the different objects, perhaps as they presented themselves in their dissections. But these 
terms were soon found to be so vague and uncertain, that it became necessary to take into consideration the form of the muscles, 
and to name them, as far as could be done, from their likeness to particular figures, calling one triangular, another rhomboid, 
quadrilateral, or pyramidal; and this appeared sufficient for the purpose intended, as far as it went, but comparatively few 
objects could !><• brought within its limit. When anatomists began to understand the powers and uses of the different muscles, 
they naturally sought to name them from a consideration of their actions, calling some flexors, others extensors, — some Adductors- 
others abductors ; — and lastly, we find some muscles named from the direction of their fibres— orbicular, transverse, oblique, or 
ascending ; and not a few from the points to which their ends are attached, ex. gr. steino-mastoid. sterno-hyoid, 

3 



4 



Muscles seldom act singly, — two or more usually conspire to execute movements apparently simple. Those which act 
logether are called associates; and when one group habitually reverses the action of another, they are called antagonists. The 
muscles seen on the fore-arm, and which, by several tendons or white cords, are prolonged through the palm of the hand to the 
bones of the fingers, curve or bend the joints of the latter, and are therefore named flexors ; whilst those at the back part 
straighten or extend them, and are called extensors. Whilst either of these motions is being executed, it might be supposed that 
only one group of muscles, ex. gr. the flexors, is in action, the extensors being quiescent : but this is not exactly the case ; for 
when we desire to bend the fore-arm, the will directs through the nerves, towards the flexor muscles placed upon the fore-part 
of the upper arm (and where they are readily felt as they come into action), a sufficient quantity of nervous influence to enable 
them to move the limb from point to point, through the arch of a circle, which it describes in passing from the straight to the 
bent position. Now, during the progress of this motion, the extensors also are kept in a state of tension, though in a less degree • 
for they are made to give way just so many points as the action of the flexors requires, yet still to hold on so as to moderate it, 
and at the same time give steadiness to the whole limb. 

By referring to plates XLVIII. and XLIX., each of the long muscles will be found attached by its extremities to particular 
points of the bones. The upper end is that by which they most usually hold fast while they pull on the lower ; hence the 
latter point is technically called the point of insertion, the former of origin. This line of action, however, is very often reversed. 
For instance, in the standing posture, a continued effort is required to keep the leg erect upon the foot ; and to effect this, the 
muscles on the fore-part of the limb take their fixed points below, upon the back of the foot and toes, from which they draw 
upon the bones of the leg, so as to hold them forward and retain them erect upoii the arch of the foot. 

How easy and simple a movement that appears to be by which we rise from the sitting 
posture and assume the erect attitude ! and yet it is executed by a series of efforts, requiring 
the co-operation of a great many muscles, and this, too, after a preparatory movement not 
a little complex in itself. In the first place, the foot is thrown backwards, and the body 
inclined forwards, in order to bring the centre of gravity directly over the basis of support : 
then the flexor muscles in the sole of the foot draw on the toes, and press them against the floor, so 
as to fix the foot ; after which, by a simultaneous effort of several muscles, the leg is made to move 
backwards, and the thigh forwards, until both become erect. During this change of position, the leg 
moves through an arch of a circle, whose centre is at the ancle-joint, the bones of the leg repre- 
senting its radius. As in this case the centre is fixed, the arch described is a part of the circum- 
ference of a circle. But the thigh-bone is differently circumstanced ; its centre is at the knee, and 
necessarily changes place so as to pass from point to point through the arch b c, whilst its change 
of position is being effected. Hence, if it is considered as a radius, it will tend to describe as 
many circles as there are points in the arch be; but it will really describe, not a part of a 
circle, but a curve, indicated by a line drawn through those points of the circumferences of the 
circles here indicated, which lie along the interval between its previous position d, and its 
present one e. If from d a line be drawn obliquely forwards, so as to represent the position of 
the body during the preparatory movement, it will be evident that the spine also resembles a 
radius attached to a moving centre at the hip-joint, and that the head, as it is ascending, will 
move in a curved line, similar to that here indicated, but described in the opposite direction. 

Plate I. is intended to exhibit the intimate composition of muscle, with a view to explain the theory of its action. Fig. 1, 
2, 3, are taken from the plate which accompanies the Memoir on Muscular Action, by MM. Prevost and Dumas, (Journal de 
Physiologic, torn, iii.) Fig. 4, 5, 6, and 7 are drawn from preparations in the Museum of the University. Each muscle, however 
simple its action may be, is in itself a compound structure : it has arteries, which convey to it blood for its growth and nutrition - 
veins, which return the residue of the blood,— nerves, forming cords of communication with the brain, or spinal marrow -and 
absorbing vessels, which perform an important part in the different changes which the process of growth and nutrition require 
All these are held together by a delicate animal substance, called cellular tissue, which also forms their bond of connexion with 
the proper fibres ot the muscle. Fig. 4 and 7 represent back and front views of the flexor muscle of the arm. The muscular, 
or fleshy part, forms a tapering body, from which white tendons, or cords, pass upwards over the shoulder-joint to the blade- 
bone, or scapula, and downwards over the elbow, to the bone of the fore-arm: it is railed biceps, from having two heads, or 
extremities at its upper end; between these the nerve is seen branching off into filaments amongst the muscular fibres. In 
fig. 5 the fibres run obliquely into one side of a tendon, upon which they act like so many cords attached to a rope passing over 
a pulley. In fig. 6 they are placed at both sides of the tendon, like the fibrilhe on a quill-feather. If the dark lines in the 
drawinp were coloured red, so as to resemble flesh, the tendons at the end being made of a pearl white, they would represent, 
as nearly as may be, the muscles m their natural condition. When by an act of the will, propagated along the nerve, a muscle,- 
the biceps, lor instance (fig. 4)-,s put m action, its body shortens and swells, its ends are brought nearer, and the fore-arm is 
drawn upward,- mto the bent pos.non. Tlus can be felt and seen whilst the effort is being made. It will very naturally be 




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asked, what is the change of state which occurs in a muscle whilst thus passing from repose into action, and what produces the 
change ? Many expedients have been resorted to, and many efforts have been made at different times, to determine these 
points ; but the best conducted and most recent researches are those of MM. Prevost and Dumas, (Journal de Physiologic, torn, 
iii.) ; yet even these are far from conclusive. A thin, flat muscle, (rectus abdominis,) taken from a frog, and placed under the 
object-glass of a microscope, appears to consist of fibres, cylindrical in their form, and straight whilst in the quiescent state, fig. 1 ; 
but when they are irritated, or acted on by electricity, they are thrown into waving, zig-zag lines, and necessarily shortened. 
By frequently repeating this observation, it is found that the angles, or points of inflexion, always occur at those places in which 
the muscular fibres are crossed by nervous filaments, (fig. 3.) Here a new question arises — what is the relation which subsists 
between the nerve and the muscle ? When a nerve is traced into a muscle, it gives off delicate branches, most of which pass 
across the muscular fibres ; but they soon become so small as to escape our unassisted vision, particularly in the large muscles of 
the higher animals, (fig. 7.) But when with the aid of a microscope, as in the experiment already noticed, the muscle of one of 
the lower animals — for instance, the frog — is examined, nervous filaments will be found at first running between the muscular 
fibres, and at intervals giving off filaments, which pass across them, and finally returning back in the form of loops, or joining 
with a neighboring branch, (fig. 2.) Most nerves convey two endowments, the power of motion and sensation; or rather, they 
are the means of imparting to muscles, not only the impulse which determines motion, but also of carrying back from them 
intimations of their condition and of their various changes of state. The former of these is effected by nervous filaments 
connected with the fore-part of the spinal marrow, and the latter by those attached to the back part ; for it has been fully proved, 
lhat the power of motion is lost when the anterior roots of the nerves, or the corresponding part of the medulla, is injured, and 
that sensation is destroyed if the like happens to the posterior. The nerves then as chordae internuncios may be likened to 
conductors, along which an influence flows from the brain and spinal marrow to the muscles, determining their contraction, and 
in the opposite direction from the muscles to the brain, conveying impressions and exciting sensations. So far we can proceed 
securely enough ; but a step farther leads at once into the region of hypothesis, where our only guide is a forced and questionable 
analogy. Observation, as above stated, having shown that when a muscle is irritated, its fibres are thrown into zig-zag lines, 
the angles of inflexion being at the points where they are crossed by the nervous filaments, and the experiments of M. Ampere 
having determined the fact, that two parallel wires will approach one another when voltaic currents pass along them in the 
same direction, Prevost and Dumas place these two pieces of information together, and found upon them a rationale of muscular 
action : — reasoning in this way, that as the wires approach one another when the voltaic agent passes along them, so the trans- 
verse filaments of the nerves become approximated when they become the conductors of the nervous influence ; and that as 
they incline towards one another, they ripple and shorten the muscular fibres. It is, however, fairly admitted, that in this mode 
of viewing the subject, the muscle itself appears to be passive and the nerves alone active. 

It may be further added, that as we should not in any case take analogy for identity, so when reasoning on phenomena so 
widely dissimilar, we are not warranted in rigorously transferring a rule from the one to the other. 

We have spoken of the bones as passive instruments; they in fact resemble levers acted on by the muscles, and in the 
human skeleton we can point out instances of the three orders of levers described by writers on dynamics. When we observe 
how the base of the skull rests on the spine as its support, and how the muscles attached to the occiput can raise the face which 

PLATE I. 

Fig. 1, gives a magnified view of muscular fibres in the state of repose. The white lines indicate the course of the nerves : as they run 

along, they give off delicate filaments which cross the fibres of the muscle. 
Fig. 2, shows how the ultimate filaments of the nerves are disposed. After branching out for some way, as in Fig. 1, they become 

curved, and return into themselves, forming loops ; or they incline towards a neighbouring branch, and form inverted arches. 
Fig. 3, represents the fibres in the state of contraction, when they are thrown into waving zig-zag lines. The transverse nervous 

filaments will be seen crossing them at the angles of inflexion. 
Fig. 4, is a front view of the biceps flexor. Fig. 7, a back view of the same. The branches of the nerve are seen ramifying amongst the 

muscular fibres. 
Fig. 5, is a semi-penniform muscle. 
Fig. 6, is a double penniform muscle, the fibres being placed at each side of a central tendon, like the fibrillte of a quill-feather. In Fig. 

5, the fibres are at one side only. 

PLATES XLVIII. & XLIX. 

Plate \ l,\ III. Inn, ling the frontispiece to this work, and Pfate XLIX. with which this section of the work concludes, exhibit the mua I. a 
sis Ihej are brought into view by the removal of the skin, with the membranous and adipose layers placed beneath it B 
from v iews are given, and in each the deeper seated as well as the superficial muscles are shown. 



6 

in front, we recognise a lever of the first order, the moving power being at one end, the weight at the other, and the 
prop between them; again the leg rests on the foot, and the strong muscles of the calf of the leg are fixed to the heel, so as to 
raise the body forward on the toes, so that the prop is at one end, (the toes,) the power at the other, and the weight in the middle, 
—being an instance of the second sort of lever. Lastly, the muscle (biceps flexor) which runs along the upper arm is fixed into 
the outer bone of the fore-arm a little below the bend of the elbow, so as to act on the fore-arm and draw it into the bent position. 
In this case, the weight or resistance (viz. the hand and arm) is at one end, the prop at the other, (in the elbow-joint,) and the 
moving power between them, exemplifying the arrangement which obtains in levers of the third order. A loss of power 
necessarily results from the adoption of this principle, but it is more than compensated by the increased quickness of movement 
which is acquired. 



PLATE II. 

The first drawing in this plate gives a front view of the muscles of the face, the skin and cellular tissue which lies under it, 
— and the vessels and nerves being removed in order to show distinctly the direction of the muscular fibres and their points of 
attachment. At the right side of the face all the muscles are allowed to remain in their natural position ; but at the left, some 
of them are removed so as to bring into view some which would otherwise remain concealed either wholly or in part. The 
occipito-frontalis muscle No. 1, is reflected obliquely upwards from off the forehead so as to expose No. 4. The orbicularis 
palpebrarum No. 3, is taken away to show the eye-lids, and their tendon No. 20, as well as the tendon of the muscle which 
raises the upper lid, (levator palpebral superioris.) Nearly the whole length of this muscle is concealed within the orbit; a small 
part, however, No. 5, projects beyond its margin and is fixed into the cartilage of the upper lid. Nos. 8, 9, 10, and 11 are here 
also left out, in order to show more distinctly Nos. 7, 12, and 13. The second figure shows the back part of the head, covered by 
the occipito-frontalis muscle No. 1. Both are taken from Cloquet. 

As the two lateral halves of the body are symmetrical, the muscles and other structures at each side of the middle line so 
perfectly correspond, that such remarks or references as are made with regard to the one will necessarily apply to the other. 

Each bundle or layer of fibres, here exhibited and marked with figures, is a muscle or moving power capable of acting in 
obedience to the will, and, when put into action, of contracting and shortening itself. As all these muscles are in intimate con- 
nection with the skin which rests upon them like a thin covering, they can so act on it as to make it assume various changes 
dependent on their form and size, on the direction of their fibres, and still more on their acting singly or in combination. Thus 
No. 1 consists of fibres which run down from the top of the forehead to the eye-brow. They are obviously continuous at their 
upper ends with a thin tendon, which, in the form of a layer of white membrane, rests upon the arch of the skull, and extends 

PLATE II. 

Fig. 1. No. 1. The fore-part of the occipito- frontal muscle, (m. epicranius.) 2. The same, detached and everted, so as to expose tin; 
bone. 3. The orbicular muscle of the eye-lids, (m. orbicularis palpebrarum ; m. orbiculaire des paupieres.) 4. The corrugator of 
the eye-brow, (m. corrugator supercilii; m. sourcilier.) 5. Part of the elevator of the eye-lid seen as it projects beyond the border 
of the orbit, and descending to be inserted into the cartilage of the lid, (m. levator palpebrae superioris ; m. elevateur de la paupiero 
superieure.) G. The pyramidal muscle of the nose, (m. pyramidalis nasi ; m. fronto-nasal.) It appears like a continuation of the 
occipito-frontal muscle. 7. The triangular muscle of the nose, (m. compressor nasi ; m. sus-maxillo-nasal.) 8. The elevator of the 
upper lip and wing of the nose, (m. levator labii superioris alseque nasi ; m. grand sus-maxillo-labial.) 9. The elevator of the upper 
lip, (in. levator labii superioris; m. moyen sus-maxillo-labial.) 10. The small zygomatic muscle, m. zygomaticus minor ; m. petit 
zygomato-labial.) 11. The large zygomatic muscle, (m. zygomaticus major; m. grand zygomato-labial.) 12. The elevator of the 
angle of the mouth, (m. levator anguli oris ; m. caninus ; m. petit sus-maxillo-labial.) This is distinctly seen at the left side as it 
descends from the upper jaw-bone to the angle of the mouth. 13. The buccal or cheek muscle, called also the buccinator or trum- 
peter's muscle, (m. buccinator ; m. alveolo-labial ;) it is more distinctly shown at the left side. 14. The masseter muscle, (m. massetrr ; 
m. zygomato-maxillaire:) it is one of the elevator muscles of the lower jaw. 15, 15. The orbicular muscle of the mouth, (m. orbicu- 
laris (iris ; m. labial :) its form is properly that of an ellipse, and the two references are used to mark its upper and lower segments. 
16. The depressor muscle of the angle of the mouth, (m. depressor anguli oris ; m. triangulaire des levres.) 17. The depressor of 
the lower lip, (m. depressor labii inferioris ; m. quadratus menti ; m. mento-labial.) 18. The elevator of the chin, (m. levator menti ; 
levator labii inferioris.) 19. The bones of the side of the head. 20. The tendon of the eye-lids, and of their orbicular muscle. The 
muscle is removed to show the tendon and the lids more distinctly. 

Fig. 2. Gives a view of the back of the head. The occipito-frontal muscle Temains in its natural position at one side, No. 1. At the 
other it is detached and drawn upwards. 2. The thin aponeurosis, which connects the occipital witli the frontal part of the muscle as 
seen in fig. 1. No. 1, rests upon the skull, and slides smoothly over it. 3. The posterior muscle of the ear, (m. retrahens aurem ; m. 
mastoido-aurieulaire.) 



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to the back of the head, where by means of muscular fibres it is attached to the curved ridge seen on the bone, on a level with 
the ear, fig. 2, No. 1. Now, when this muscle is put into action, in the first instance it draws up the eye-brow, and if its effort is 
carried further it throws the skin of the forehead into transverse folds or wrinkles. 

The lower end of these fibres will be observed to be connected along the line of the eye-brow with those of No. 3, and 
there they conceal a little muscle such as is seen at the left side No. 4 ; at the root of the nose the fibres of No. 1 are prolonged 
down for some way, and become attached to the bone. To form a clear idea of the 'form, extent, and structure, of this muscle, 
just for a moment suppose a piece of wire, or a long needle, to be introduced beneath its inner border, half an inch above the 
root of the nose, and pushed outwards close to the bone until it protrudes at the temple ; and this can be readily done when the 
parts are dissected, as it merely rests on the bone. Then, by holding the two ends of the wire, it may be made to pass from 
before backwards, so as to slide under the muscle as far back as the occiput. By this expedient it may be shown that the muscle 
consists of two fleshy portions connected by a thin tendinous membrane. One fleshy part rests on the forehead, (fig. 1, No. 1,) 
and the other on the occiput, (fig. 2, No. 1.) All the parts of this muscle are intimately connected with the skin, while they slide 
smoothly over the skull ; and, as the fleshy fibres at its opposite ends can be put alternately in action, we can readily conceive 
how it is that persons in whom it is much developed can move the hairy scalp, and draw it forwards and backwards at pleasure 

No. 3 {orbicularis palpebrarum) is a flat plane of circular or elliptic fibres placed round the eye-lids, but extending at the 
same time upwards on the brow and downwards on the cheek. Between the upper and lower segments of the muscle is the 
transverse fissure which separates the eye-lids, and through which the globe of the eye projects. This muscle is not concerted 
"with the bones of the face at any point of its extent except towards the inner border of the orbit, where it becomes attached by 
means of a small white tendon, (similar to that seen at the left side No. 20,) and also by some of its own fibres, which are fixed 
a little above the tendon. But the upper part of the muscle which lies along the eye-brow is intimately connected with the fibres 
of No. 1 which lies above it, and with No. 4 which is placed under cover of it. The corrugator supercilii No. 4, when brought 
into view by removing No. 3, appears in the form of a small tapering bundle of muscular fibres, attached by its inner end to the 
bone, whilst the other becomes blended with the two preceding muscles. Now, when No. 3 is thrown slightly into action, it 
contracts and shortens in such a way that the fibres of the upper and lower segments become straight and approach one another 
so as to close the eye-lids. If this action is continued and becomes forcible, the lids become wrinkled and drawn at the same 
time inwards to the root of the nose, by which means the tears, and any extraneous matters which may rest upon the eye-ball, 
are carried to the inner angle of the orbit, whence the lachrymal ducts lead to the nose. If No. 1 raises the brow and wrinkles 
the skin of the forehead transversely, this muscle can draw it downwards and undo the creases. 

Let the reader for a moment conceive that he can lift up this muscle from the parts on which it lies by passing a wire under 
its external border, where it rests on the cheek-bone, and then gradually detaching the lower segment of it from the bone and 
the muscles 8, 9. The upper segment may also be separated along the eye-brow, although with more difficulty, as it is connected 
intimately with No. 1. If a piece of card be then placed under it, it will represent what we have stated it to be : viz. a flat 
plane of elliptic fibres, which are not connected with the bones of the face at any part of their extent except at the inner border 
of the orbit. At this point will be observed a small white line, representing a tendon, whiqh runs horizontally outwards from 
the side of the nose to the fissure of the eye-lids. It is marked at the left side No. 20 ; it can be readily felt under the skin by 
drawing the lids outwards, so as to make it tense. To this tendon some of the muscular fibres are attached, and others are con- 
nected with the bone higher up towards the root of the nose. 

No. 4, by its direction and point of attachment, is enabled to draw the eye-brow inwards, and throw it into vertical folds, as 
in frowning : but in this action the inner part of the upper segment of No. 3 exerts a considerable influence : for the brow is 
obviously drawn downwards in the direction of the tendon or fixed point of this muscle, as well as inwards to the root of the 
nose. 

We proceed in the next place to the muscles of the mouth. The transverse fissure between the lips is here observed to be 
surrounded by a flat plane of elliptic fibres, {orbicularis oris,) No. 15, in most respects similar to those of the eye-lids. By a 
slight degree of contraction they close the lips, and when they act a little more forcibly they crease the skin, and render the 
aperture small and circular, like the mouth of a purse, when its string is drawn tightly. To this, as to a common centre, several 
bundles of fibres, forming so many separate muscles, will be observed to converge from different points. Nos. 8 and 9 run down- 
wards from the margin of the orbit; Nos. 10 and 11 incline obliquely from the cheek-bone. No. 13 inwards from the checks. 
Nos. 16 and 17 upwards from the lower jaw-bone. The ends of these muscles which are most distant from the mouth are 
attached to the bones here named, as to so many fixed points; but the other ends are united to the circular muscle round the 
mouth. Now all these may be considered as so many retractors, which can draw the lips either upwards, downwards, outwards, 
or obliquely upwards. If No. 8 acts by itself, it draws up the lip and the wing of the nose, for three or four of its fibres will lie 
seen attached to the most prominent part of the side of the nose. No. 9 draws the middle of the lip also upwards : No. 12 ele- 
vates its angle : Nos. 10 and 11 draw the angle outwards and upwards, whilst 16 depresses it : No. 17 draws down the lower 
lip. It is by the agency of these different moving powers that the face can exhibit all that variety of expression of which it is 
susceptible. The forehead and brow, now calm and placid, can instantly be made to assume the frown of aversion or contempt. 



8 

And tin' lipa which slightly move as we speak, or at times open into a smile, may with the rapidity of thought exhibit all the 
varieties of expression which characterise joy and grief, hope and despair, the tenderness of affection, or the bitterness of scorn. 

Tha different muscles here noticed receive branches from a nerve (facial,) which serves as the means of connecting them 
with the brain, and placing them under the control of the will. This nerve, after passing down through the base of the skull, 
lies at first deeply in the interval between the ear and the angle of the jaw, where it soon divides into long filaments, which branch 
out upon the side of the face, some mounting upwards upon the temple, others inclining down along the lower jaw and the throat, 
whilst more proceed across to the cheek, nose, and lips. To this nervous cord and its branches, the muscles of expression owe 
their power of action. If it be compressed by a tumour, or divided during the progress of a surgical operation, the muscles 
become paralyzed, and lose the power of motion and of expression. Whenever this occurs, the muscles of the sound side being 
no longer counteracted, will draw on the mouth and lips, and cause a permanent deviation. The influence of nervous action 
upon the muscles is thus rendered obvious. Now, as the expressions of the face are put on in obedience to the promptings of 
tin will, or the impulse of passion, they form so many outward indications of inward feeling ; and as in many instances they are 
so often repeated as to become habitual, they give a certain cast to the countenance indicative of the prevailing habits of the 
mind. 

In the features of an empassioned countenance, (observes Sir C. Bell, Anatomy of Expression,) it is not upon a single feature 
that the emotion operates, — there is a consent and accordance between different parts, — the whole face is marked with expres- 
sion, and all its movements are consentaneous. " Hence when the angles of the mouth are depressed in grief, the eye-brows are 
not elevated at the outer angles, as in laughter. When a smile plays around the mouth, or the cheek is elevated in laughter, the 
brows are not ruffled, as in grief. The character of such opposite passions are so distinct that they cannot be combined, where 
there is true and genuine emotion. When we see them united by those who can, at will, control the actions of their muscles, the 
expression is farcical and ludicrous." 



PLATE III. 

The third plate gives a view of the muscles which lie immediately beneath the skin, upon the front and side of the neck. 
To render these apparent, the tegument and the superficial fascia are removed, and the cellular tissue which fills the interstices 
between the muscles is dissected out ; moreover, the deep or proper cervical fascia is taken away, in order to exhibit the forn 
and size of the different muscles, as well as the direction of their fibres. 

In fig. l, a broad but very thin layer of pale fibres, No. 4, will be observed to run up from the top of the chest and front ot 
the shoulder, over the clavicle, and along the side of the neck, to the lower jaw and the cheek. From the paleness and thinness 
of its fibres, it is evident that its power is very little in the human subject ; it may be considered a rudiment of the extensive 
fleshy layer which lies under the skin in lower animals, and enables them to move it to and fro, as well as to wrinkle it, and 
thereby remove any irritating substances which may rest upon it. It is called platisma myoides— the broad muscle-like 
lamella, (/wan a muscle, »«o S like.) Underneath this, and partly concealed by it, the extremities alone being uncovered, is a long, 
thick (and towards the middle, rounded) muscle, which lies obliquely along the neck at each side, being stretched from the sternum 
and clavicle, (the breast-bone, and collar-bone,) up to the bony prominence the mastoid or nipple-shaped process, (twxot a nipple, 
*•*»« like,) behind the ear. Its name expresses its three points of attachment, viz. sterno-cleido-mastoid. Its lower end consists 
of two parts, differing in their form as they do in the parts to which they are fixed ; one being rounded and cord-like, the other 
flat and somewhat triangular ; the former arises from the sternum, the latter from the clavicle. These are at first separated by 
a slight interval filled by cellular tissue, but they soon become united. The two muscles of this name will be observed to be 
close together at their lower ends, fig. 1, No. 3, and widely apart at the upper ends, where they are fixed to the base of the skulL 
\\ hen they both act together they bow the head, by drawing it downwards and forwards towards the chest, which is the point 
from which they act ; if one of them acts by itself, it draws the head downwards to its own side, but it is also enabled by the 
obliquity of its direction to give a horizontal movement to the base of the skull, so as to turn the chin round towards the shoul- 
der of the opposite side. Thus the right sterno-mastoid muscle, fig. i, No. 13, can rotate the head, and turn the chin to the left 
side, until it comes into the position seen in fig. 2. 

Two flat, ribbon-shaped muscles are here shown, No. 15, lying beside one another, at the front and side of the windpipe, 27, 
and organ of voice, (larynx,) No. 23. They stretch upwards from the sternum (its inner surface) to the tongue-bone, (os linguale, 
also called hyoides, or U-shaped, from some likeness to the Greek letter fc Hence they are named sterno-hyoid muscles. Their 
action is obvious; they draw down the base of the tongue, and are therefore the antagonists of the muscles, which, by being 
stretched from the lower jaw to the tongue-bone, are so many elevators, (22, 23.) Close to the outer border of 15 is another flat, 
but still narrower band, 14 ; part of it is seen running obliquely up from behind 16, to the tongue-bone ; part is concealed by 



Muscles 



r/ate 3 











9 

1G, and another part, marked 13, lies still lower down, where it is deeply seated, and runs behind the clavicle to the upper border 
of the scapula, or blade-bone; it is named omo-hyoideus, («/»<« the shoulder:) it too is a depressor of the tongue-bone. At the 
external border of 14, and partly concealed by it, is a short, flat muscle, which extends from the side of the thyroid cartilage, 
(24,) to the side of the tongue-bone; its name expresses its attachments — thyro-hyoi'd. It draws down the root of the tongue, 
if the thyroid cartilage is previously fixed, or it will carry the latter upwards, when the tongue-bone is drawn up by the action 
of the muscles, which connect it with the lower jaw and the base of the skull. 

We shall, by and by, see the importance of this movement during the effort of swallowing: it will be found that it draws 
the entrance into the air-passages upwards, in such a way as to place it securely under the protection of a valve, or coverlid, (the 
epiglottis,) which prevents the descent of food or fluids into it. Part of a muscle is here also seen at the outer border of the 
sterno-hyoi'd, by which it is overlapped ; it comes up from the sternum, and is fixed to the side of the thyroid, or shield-shaped 
cartilage, (Ove,w a shield,) which it draws down if previously elevated. 

Beneath the lower jaw are seen three muscles, which differ in form and size, as well as in the direction of their fibres. 
Two of them incline down from the base of the skull to the tongue-bone. In fig. 2, they appear deeply placed behind the angle 
of the jaw. One of them, fig. 2, No. 18, is round and tapering, its upper end is attached to a long bony process, which from 
some resemblance to the ancient stylus, or writing-instrument, has been called " styloid." The lower end of the muscle is fixed 
to the hyoid bone ; hence its name stylo-hyoid. Close to the stylo-hyoid muscle, is one which consists of two parts or bellies 
united by a round teudon, and which is called digastric or double-bellied. One part, No. 20, is inserted close under the chin ; 
the other lies deeply, being concealed by the sterno-mastoid muscle : the tendon which connects the two runs through a slit in 
the fibres of the stylo-hyoid muscle, by which means, as well as by some dense white fibres, it is connected with the hyoid bone. 
The whole muscle thus forms an arch whose concavity looks up to the jaw-bone. Suppose the jaw to be fixed as when the 
mouth is closed in the preparatory effort of swallowing, and that this muscle is put in action, its fibres when contracted and 
shortened will bring both its parts from the curved into the straight direction, by which means it will draw up the tongue-bone ; 
the stylo-hyoid muscle will assist in the effort. The anterior part of the digastric muscle is seen to rest upon a flat plane of 
muscular fibres which pass down from the lower jaw, inclining obliquely inwards as they descend. Close under the chin, the 
fibres belonging to the muscles of opposite sides meet and join ; and this convergence and union takes place along the whole 
interval between the chin and the tongue-bone, into which the longest fibres are inserted. The upper end of the fibres is fixed 
to the inside of the jaw-bone, the lower into the tongue-bone ; whilst in the interval between the latter and the chin, the fibres 

PLATE III. 

Fig. 1, exhibits the muscles seen upon the front of the neck, after the skin and fascia have been removed. No. 1, the border of the lower 
jaw-bone seen in front. 2. The clavicle of the right side; that of the left is partly concealed by the platisma muscle. 3. The 
sternum. 4. The platisma myoides muscle, (musculus latissimus colli; m. peaucier.) 5. The elevator muscle of the chin, (m. 
levator menti.) 6. The depressor of the lower lip, (m. quadratus menti ; m. mento-labial.) 7. The depressor of the angle of the 
mouth, (m. triangularis oris.) 8. The buccinator muscle, (m. buccinator: alveolo-labial.) 9. The masseter, (m. masseter; zygomato- 
maxillaire.) 10. The sterno-cleido-mastoid muscle. 11. Jaw-bone. 12. Part of the trapezius muscle, (m. cucullaris; occipito-dorsi- 
sus-acrornien.) 13. The lower part of the omo-hyoideus muscle, (m. scapulo-hyoideus.) 14. The upper part of the same muscle, the 
intervening portion being concealed by the sterno-cleido-mastoid. 15. The sterno-hyoid muscle, (m. stemo-hyoideus.) 16. The 
tongue-bone, (os hyoides; os linguale.) 17. The thyro-hyoid muscle, (m. thyro-hyoideus.) 18. The large wing, (cornu,) of the 
hyoid bone. 19. Part of the stylo-hyoid muscle. 20. The posterior part of the digastric muscle, (m. digastricus ; m. mastoido- 
mentale.) 21. The anterior part or belly of the same muscle. 22, 22. The mylo-hyoid muscles of the opposite sides, (m. mylo- 
hyoideus;) their fibres are seen converging, so as to form a seam by their junction, along the interval between the chin and the hyoid 
bone. 23. The shield-shaped, or thyroid cartilage, (dv^ov a shield, ftSo? like,) forming the most prominent part of the orofan of voice. 
24. The cricoid, or ring-shaped cartilage, (xifxoj a circle,) which forms .also a part of the organ of voice. 25. A small plate of 
mttnbrane, (crico-thyroid,) connecting the two parts last named. 26. The thyroid gland. 27. The windpipe or trachea. 28. The 
inter- clavicular ligament, a strong band stretched across the top of the sternum from one clavicle to the other. 29. Part of the great 
pectoral muscle. 30. Part of the deltoid muscle. 
Fig. 2. Shows the muscles upon the side and front of the neck; the cutaneous or platisma muscle, together with the integument, have 
been taken away. No. 1. The occipital bone. 2. The mastoid or nipple-shaped process of the temporal bone, in great part concealed 
by the insertion of the sterno-cleido-mastoid muscle. 3. The tube of the ear. 4. The angle of the lower jaw-bone. 5. The sym- 
physis or junction of the same bone. 6. The clavicle. 7. The sterno-cleido-mastoid muscle. 8. Its clavicular part or region. !). 
Part of the trapezius muscle. 10. The splenitis muscle (m. splenitis colli et capitis; m. cervico-mastoide et dorso-trachelien.) 11. 
Part of the elevator of the scapula (m. levator anguli scapulae; m. trachelo-anguili-scapulaire.) 12. Tin- posterior scalenus mi 
13. The lower part of the omo-hyoid muscle. 14. The upper part of the same muscle, 15. The sterno-hyoid muscle. 16. The 
thyro-hyoid muscle. 17. Part of the sterno-thyroid muscle. 18. The stylo-hyoid muscle. 19. 20. The two parts or bellies of the 
digastric muscle. 21. Some tendinous fibres which connect it to the hyoid bone. 22. The mylo-hyoid muscle. 23. The hyoid or 
lingual bone. 24. The thyroid cartilage. 25. The thyroid gland. 26. The trachea or windpipe. 27. The interclavicular ligam 
28. Part of the great pectoral muscle. 29. Part of the deltoid muscle. 
Muscles. — 2 



10 

converging from opposite sides of the middle line join so as to form a sort of seam, (see plate V. fig. 4.) Its name "mylo-hyoid," 
- poinU of attachment to a slight ridge at the inner side of the jaw near the grinder teeth (pi*» s a grinder) and the 
hyoid bone. It assists other muscles in drawing up the base of the tongue; and as it is placed immediately under the lining 
membrane of the mouth, it may be said to form a floor for that cavity, which, by the relaxation of its fibres, permits it to 
descend and become deep,-and by their contraction draws it up again when circumstances require, so as to make it nearly a plane 
surface. 

At the outer border of the sterno-mastoid muscle, fig. 2, Nos. 7, 8, is a deep interval intervening between it and the trapezius, 
No. 9. In this space will be seen, towards its lower part, the omo-hyoid muscle 13, resting on another, the middle scalenus 12 ; 
higher up arc the fibres of the splenius and levator scapulae, (Nos. 10, 11.) These shall be commented on in a subsequent 
page. 



PLATE IV. 

These drawings exhibit different views of the canal or passage which leads from the mouth and nose downwards into the 
stomach and lungs : it is, in technical language, called the pharynx ; it is thin and membranous in its structure, being made up 
of two layers, the one a mucous membrane continuous with that which lines the mouth and nose, and which is prolonged 
throughout the whole alimentary canal — the other a layer of muscular fibres, disposed in a very peculiar way, which not only 
supports the lining membrane, but also gives to the tube itself a contractile power. The pharynx thus formed may be called a 



PLATE IV. 

Figs. 1 and 2. Exhibit the pharynx and its muscles, as seen from the back. The arch of the skull is altogether removed, and only a part 
of its base remains. In order to obtain this view of the pharynx, it must be detached from the spine, in front of which it lies, and the 
fore-part of the skull must be separated from the back-part, in such a way as to leave the pharynx hanging down from the base of the 
skull. For this purpose, the trachea and oesophagus must be cut across at the lower part of the neck, near the sternum, and then 
drawn forwards and upwards ; after which there is no difficulty in detaching the pharynx from the muscles in front of the spine, as it 
is connected with them merely by some loose cellular tissue. In the next place, a piece of linen, or calico, to serve as a retractor and 
guard to the pharynx, is to be passed down into the narrow interval between it and the top of the spine, and drawn tightly 
forwards, so as to protect the pharynx. The saw is to be inserted close to the cloth, in such a way that its edge shall rest immediately 
behind the roots of the styloid processes, and cut through the base of the skull from below upwards. By these means the pharynx, 
with that part of the base of the skull to which it is attached, is severed from its connexions with all contiguous structures, and can 
he examined by itself. 

One such section will furnish readily the three views seen in figs. 1, 2, 3, and a very little management will suffice to obtain the 
lateral view given in fig. 4. 

Fig. 1. No. 1. Part of the basilar process of the occipital bone. 2, 2. The petrous part of the temporal bone. 3, 3, The mastoid 
process of each side. 4, 4. The styloid process of each side. 5, 5. The lower jaw-bone. 6, 6. The extremities of the horn-shaped 
processes of the tongue-bone. 7. The border of the thyroid cartilage. 8. The rings of the windpipe. 9. The internal pterygoid 
muscles passing down from the groove between the pterygoid processes of the sphenoid bone, to be inserted into the angle of the 
lower jaw-bone. 10. The inferior constrictor muscle of the pharynx, (m. constrictor inferior.) At the opposite side the muscle is 
removed, in order to expose the lower part of the middle constrictor, which it conceals, and also the insertion of the stylo-pharyngeus 
muscle into the thyroid cartilage. 11. The middle constrictor muscle, its fibres spreading away like the ribs of a fan from their 
common origin at the tongue-bone, and passing back to unite with the corresponding muscle of the opposite side, and form a raphe, 
or seam, which is here seen to run from below upwards to the base of the skull. 12, 12. The superior constrictor muscles of each 
side, (m. constrictor superior.) The upper border of each is observed to be slightly curved, and as the upper fibres pass from the 
pterygoid process to the base of the skull, they necessarily leave a small part of the mucous membrane uncovered. 13, 13. The 
stylo-pharyngeal muscle of each side, (m. stylo-pharyngeus.) As the fibres descend they are observed to spread out a little; they 
become concealed by the middle constrictor, and also by the inferior constrictor; they finally terminate, 14, at the border of the thyroid 
cartilage. 15. The commencement of the oesophagus, where it passes down from the pharynx. 

Fig. 2. Shows nearly the same parts, the inferior and middle constrictor being taken away so as to expose the mucous membrane of the 
pharynx in the points which correspond with them, (10, 11.) By these means the stylo-pharyngeus muscle is shown in its entire 
length, and also the superior constrictor. The stylo-pharyngeus of the right side is also taken away, in order to show the attachment 
which the superior constrictor has to the inside of the lower jaw-bone, and to the ligament which is extended from that bone to the 
internal pterygoid plate. No. 1. The basilar process of the occipital bone. 2, 2. The petrous part of the temporal bone. 3, 3. The 
mastoid process. 4, 4. The styloid process. 5, 5. The lower jaw-bone. 6, 6. The extremity of the horn-shaped process of the 
tongue-bone. 7, 7. The borders of the thyroid cartilage. 8. The rings of the windpipe. 9. The internal pterygoid muscle of the 
left side. 12, 12. The superior constrictor muscles of the pharynx ; their fibres unite to form a seam along the middle line, and those 
highest up are fixed into the basilar process. 13. The left stylo-pharyngeus muscle. 14. The insertion of the same into the border 



— 



<,Musc7e<$. 



Wale 4 







11 

musculo-membranous tube ; it extends from the centre of the basis of the skull as far as the fifth cervical vertebra, where it 
terminates in the oesophagus — the lengthened passage which leads thence downwards to the stomach. As the pharynx contracts 
towards its lower part, it has been likened to a funnel, and the comparison would be sufficiently correct were it not that it is 
wider in the middle than at its upper extremity: it lies along the neck before the spine, between the great blood-vessels of the 
neck, and behind the cavities of the nose, of the mouth, and of the larynx or organ of voice, all of which open into it. Figs. 1 
and 2 show that it is closed at its back part and sides, in which situation it is found to be but loosely connected with surrounding 
structures, so that it admits of ascent and descent in the different efforts which are required in swallowing food and drink, and 
also in modulating the voice. If it be laid open as in fig. 3, by an incision made from below upwards along its back part, then 
it will be seen that it communicates with the nose by two apertures, — with the mouth by an arched interval situated between the 
root of the tongue and the palate ; also, that two lengthened ducts, called Eustachian tubes, lead outwards from it to the cavities 
of the ears :. that, in the next place, it communicates with the larynx by a narrowed aperture surmounted by a valve called the 
epiglottis ; and finally, that it narrows into a tube as it becomes continuous with the oesophagus. Its connexion with the base 

of the thyroid cartilage. 15. The tube of the oesophagus, continuous with the lower end of the pharynx, from which it is prolonged 
down to the stomach. 16. The tube of the windpipe cut across. 

Fig. 3. Brings into view the different openings and passages which communicate with the pharynx. This is readily done by laying 
opening the pharynx along its entire length, beginning below at No. 15, fig. 1, and running the blade of a pair of scissors upwards to 
the basilar process. The sides are then drawn asunder, and retained so by hooks. By these means we see the posterior openings of 
the nose, 8, 8, with the partition between them, 5. 9, 9. The opening into the mouth, the tongue 10, and the opening 11, into the 
windpipe and organ of voiee. The lining membrane is left on at the right side, but at the left it is removed so as to expose the 
muscular fibres of the pharynx, 20, and of the soft palate. The muscles of the latter at first appear complex, but their relative 
position and uses are soon rendered intelligible. The soft palate hangs down from the back part of the roof of the mouth, and is 
likened to a movable curtain ; it presents at the middle a pointed process, 16, called the uvula, and at each side an arched border. 
Two thin bundles of muscular fibres, 17, 17, (kvatores palati,) run down to it from the base of the skull, which, when put into action, 
readily draw it up. One at each side, No. 19, {palato-pharyngeus,') descends from it to the pharynx, which can draw it downwards. 
Another pair, 18, {tensor palati,) after running for some way vertically downwards, change their direction by coiling round a process 
of bone, and turn horizontally inwards, by which means they can stretch it from side to side and make it tense. Two little muscles 
are placed in the uvula, No. 16,* which shorten it. In fig. 4, a side view is given of the hard palate, No. 5, and of the soft palate 
hanging down from its back part, No. 24. (See plate V. fig. 3.) 

Having premised thus much upon the objects of the drawing, we shall now give the references seriatim. No. 1 . The basilar 
process of the occipital bone. 2, 2. The petrous part of the temporal bone. 3, 3. The mastoid processes. 4. Part of the sphenoid 
bone. 5. The partition between the right and left cavities of the nose. 6, 6. The extremities of the tubes which lead from the 
throat outwards, into the cavities of the ears. They are called Eustachian tubes, from the anatomist Eustachius. 7, 7. The extremi- 
ties of the spongy bones of the nose ; these are seen in fig. 4. 6, 6. 8, 8. The posterior openings of the nose. 9, 9. The fauces or 
narrowed communication from the mouth into the pharynx. 10. The upper surface of the tongue. 11. The epiglottis, and the 
opening into the air-passage, which it, over-hangs and protects. 12, 12. The borders of the thyroid cartilage. 13. The tube of the 
cesophagus or gullet leading down from the pharynx. 14, 14. The angle of the lower jaw-bone. 15, 15. The internal pterygoid 
muscle. 16. The azygos uvulae muscle. 17,17. The elevators of the soft palate. 18,18. The tensors of the soft palate. 19. The 
palato-pharyngeus muscle. 20. The superior constrictor muscle everted. 

Fig. 4. Exhibits a side view of the parts which are seen from behind in fig. 3. It is obtained by making a vertical section running 
from before backwards, of the base of the skull, of the roof of the mouth, of the lower jaw, and of the larynx. No. 1. Part 
of the body of the sphenoid bone, and behind it a part of the basilar process of the occipital bone. 2. The crest or cockscomb 
process of the ethmoid bone. 3. Part of the frontal bone. 4. The nasal bone. 5. The hard palate or bony roof of the mouth. 
6. The three turbinate bones which overhang and form the passages (meatus) of the nose. 7. The inner side of the dental arch. 
8. The upper surface of the tongue, and its papillae. 9. The epiglottis. 10. Part of the tongue-bone. 11. The thyroid cartilage. 
12. The arytenoid or ewer-shaped cartilage : between these will be observed an oval depression in the side of the larynx or organ of 
voice, which represents the ventricle of the larynx ; it is bounded above and below by white lines, indicating the position of the vocal 
cords. 13. Is the back part of the ring-shaped (cricoid) cartilage. 14. The section of the rings of the windpipe. 15. The lower 
jaw cut through at its fore-part or symphysis. 16. The lower lip. 17, 17. The superior constrictor muscles of the pharynx, that of 
the left side being held back by a hook. 18. The middle constrictor of the left side everted. 19. The inferior constrictor muscle. 
20. The palato-pharyngeus muscle, (m. pharyngo-staphylin.) 21. The great horn of the thyroid cartilage. 22. The lower part of 
the stylo-pharyngeus muscle. 23. Part of the middle constrictor muscle of the right side. 24. The soft palate and uvula. 
25. The palato-glossus muscle (m. glosso-staphylin, constrictor Isthmii faucium,) of the right side. 26. The elevator muscle of the 
soft palate, (m. levator palati; m. peri-staphylin interne.) 27. Part of the tensor muscle of the soft palate, (m. circumflexus vel 
tensor palati ; m. peri-staphylin externe.) 28. The Eustachian tube. 29. The genio-hyo-glossus muscle; its name expresses in 
three attachments : viz. to the inner side of the chin, (ytvetov,) to the hyoid or tongue-bone, and to the tongue itself. It is very narrow 
at its commencement at the chin, but its fibres soon spread out like the ribs of a fan, as they are inserted into the under surface of the 
tongue from its point as far back as its root. 30. The genio-hyoid muscle; its name expresses its points of attachment to the chin 
and tongue-bone. 31. The mylo-hyoid muscle. 32. A small part of the digastric muscle. 33. The skin beneath the jaw-bone. 
31. Part of the orbicular muscle of the lips. 35. The inner side of the buccinator muscle. 

* Formerly described as a single muscle, azygos uvulsc. 



12 

of the skull at its upper part is effected not merely by its lining membrane, but also by its muscular fibres, many of wbich are 
attached to the botes of the skull, and take their fixed points from them when they are called into action. These muscular 
fibres arc disposed in a very peculiar way at the sides and back part of the pharynx; there are three plates of them at each 
side, as may be seen in fig. 1, also in plate V. fig. 1. One plate, situated low down, consists of fibres which are fixed along the 
side of the larynx, from which they pass obliquely backwards and upwards, until they are met, along the middle line, by a 
similar set of fibres derived from the opposite side, where they join, forming a sort of seam, (raphe;) thus they are made to 
enclose the tube : the lowest of these fibres will be observed to arise from the first rings of the windpipe, and to run almost 
directly backwards, so as to surround the commencement of the oesophagus, whilst the upper fibres are very oblique in their 
course, so as to become nearly vertical in their direction, and these will be observed to cross and overlap part of the middle plate. 
Now the middle plate just mentioned consists of fibres which spread out from a common point, like the ribs of a fan, some 
upwards, some downwards, the rest with various degrees of obliquity, but all tending towards the back part of the tube, where 
they unite with similar fibres derived from the opposite side, just as we saw in the case of the preceding muscle. The common 
point of origin of this muscle is from the side of the tongue-bone, (see plate V. fig. 1 ;) and as they diverge whilst passing 
backwards, some of them will be observed to get under cover of the inferior constrictor and to be overlapped by it, whilst those 
placed higher up overlay in their turn the fibres of the superior one. The third or highest of these muscular lamellae will be 
observed to embrace the top of the tube ; some of its fibres commence at the inside of the lower jaw, some higher up from a 
thin ligament, (pterygo-maxillary, plate V. fig. 1, No. 20,) which passes from the internal pterygoid plate of the sphenoid bone to 



PLATE V. 

Fig. 1. Gives a side view of tin- muscles of the pharynx, showing their different points of attachment to the side of the larynx, to the 
tongue-hone, to the lower jaw, and to a ligament, No. 20, stretched between the latter and the pterygoid process, 21. The lower jaw 
is cut across near its angle, and its ascending part or branch removed." No. 1. The side of the skull. 2. The forehead. 3. The 
cheek-bone. 1. The zygomatic process. 5. The mastoid process. G. The styloid process. 7. The lower jaw-bone. 8. The uppei 
jaw-hone. 9. The tongue-bone. 10. The thyroid cartilage. 11. The great cornu, or horn-shaped process of the thyroid cartilage. 
12. The cricoid, or ring-shaped cartilage. 13. The rings of the windpipe. 14. The commencement of the oesophagus, or gullet. 
15. A broad membrane (thyro-hyoid) which connects the thyroid cartilage with the hyoid, or tongue-bone. 10. A round ligament, 
which connects the cornua of the parts last named. 17. The mylo-hyoid muscle. 18. The buccal, or buccinator muscle. 19. The 
orbicular muscle of the lips. 20. The pterygo-maxillary ligament. 21. The attachment of the superior constrictor muscle to the 
inner plate of the pterygoid process. 22. Tin external plate of the pterygoid process. 23. Part of the circumflex, or tensor musole 
of the soft palate. 21. The superior constrictor muscle of the pharynx. 25. The middle constrictor muscle. 2G. The inferior con- 
strictor muscle. 

Fig. 2. Gives a side view of the tongue and its muscles; also of those which descend from the styloid process to the side of the tongue, 
to the tongue-bone, and to the thyroid cartilage. No. 1. The side of tire skull. 2. The forehead. 3. The cheek-bone. 4. The 
zygomatic process. 5. The mastoid process. 6. The styloid process. 7. The branch of the lower jaw drawn up. The bone has 
been cut through at the chin, 7; also at its angle, and part removed, so as to expose the cavity of the mouth. 8. The upper jaw-bone. 
9. The tongue-bone. 10. The thyroid cartilage. II. Its horn-shaped process. 12. The cricoid cartilage. 13. The rings of the 
windpipe. 14. The oesophagus. 15. The external lateral ligament of the lower jaw-bone. 16. The stylo-maxillary ligament, ex- 
tended between the styloid process and the angle of the lower jaw-bone. 17. The stylo-hyoid ligament, passing from the styloid 
process to the small process of the tongue-hone. 18. The stylo-glossus muscle. 19. The stylo-hyoideus muscle. 20. The stylo- 
pharyngeus muscle. 21. The superior constrictor muscle of the pharynx. 22. Part of the inferior constrictor muscle ; the rest having 
been removed, so as to expose the insertion of the stylo-pharyngeus muscle into the border of the thyroid cartilage. 23. The thyro- 
hyoideus muscle. 24. The hyo-glossus muscle. 25. The tongue. 2G. The genio-hyo-glossus muscle. 27. The genio-hyoideus 
muscle. The names of these muscles indicate their respective points of attachment. 

Fig. 3. Exhibits the muscles of the soft palate, as seen from behind :— the upper jaw-bones, with the roof of the mouth, and a small part 
of the base of the skull, are retained. No. 1. Part of the basilar process of the occipital bone. 2, 2. The extremity of the | 
portion of the temporal bone. 3, 3. Part of the sphenoid bones. 4, 4. The posterior borders of the upper jaw-bones. 5. The partition 
between the cavities of the nose. 6, 6. The hook-shaped (hamular) processes of the sphenoid bone. 7, 7. The external pterygoid 
plates of the same bone. 8, 8. The palate plates of the upper jaw-bones. 9, 9. The Eustachian tubes. 10. The elevator muscle 
of the soft palate (m. levator palati ; peri-staphylin interne,) at the right side; that of the left is removed in order to show the entire 
extent of— II, 1 1, the tensor or circumflex muscles of the soft palate (tensor vel circumflexus palati ; peri-staphylin exteme.) 12, 12. 
The inner or reflected part of these muscles. 13, 13. The muscles of the uvula, (azygos uvulae ; palato-staphylin.) The circumflex 
muscles will be observed to turn round the hooked processes, which changes their direction, and gives them the mechanical advantage 
of a pulley, and enables them to stretch the soft palate from side to side and render it tense; the elevator muscles can draw up the soft 
palate so as to bring it to a level with the roof of the mouth or the hard palate; the little muscles of the uvula draw up and shorten 
that process. 

Fig. 4. Shows the mylo-hyoid muscle which forms the floor of the mouth. No. 1,1. The inner side of the lower jaw-bone. 2, 2. Its 
condyles. 3, 3. Its coronoid processes. 4, 4. The mylo-hyoid muscles. 5. The body of the tongue-bone. 6, G. Its great cornua 
or processes. 



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13 

the lower jaw, and others still higher from the plate of bone just named. From these different points the fibres pass backwards, 
coiling round the tube, and join with those of the opposite side, whilst those highest up are fixed into the basis of the skull, 
forming a slightly-arched border as they curve upwards ; this is seen in figs. 1, 2. When these muscles are called into action, 
they will compress the sides and back part of the tube, thereby diminishing its capacity ; hence they are called constrictors of the 
pharynx, and they are named in their order from above downwards, superior, middle, and inferior; but in describing them and 
in noting their peculiarities, we begin with that which is lowest down, for it overlaps the middle one, and the latter in its turn 
overlays that which is still higher up. The attachment of some of the fibres of the superior constrictor to the pterygo-maxillary 
ligament deserves particular attention, for it shows how the side of the mouth is connected with that of the pharynx, the ligament 
forming a bond of connexion between the muscular fibres of both. The square muscle which occupies the side of the cbeek 
arises in part from the ligament just alluded to ; so that from it, as a common point, the fibres can be traced forwards into the 
cheek, and backwards into the pharynx, (see plate V. fig. 1, Nos. IS, 20, 24.) 

The constrictors are not the only muscular fibres found in the pharynx ; two long tapering muscles will be observed to pass 
down converging into its sides. The upper ends of these muscles are attached to the styloid processes of the temporal bone, and 
as their fibres descend they get under cover of the middle constrictors, so as to lie between them and the lining membrane ; their 
lower extremities are fixed into the borders of the thyroid cartilage ; from their connections, they are named stylopharyngeal. 
There is another pair of muscles connected with the pharynx of a much smaller size, which can only be seen when the cavity 
is laid open, as is seen in fig. 3, where a thin fasciculus, (No. 19,) is seen descending from the side of the soft palate, along the 
side of the pharynx immediately under cover of the mucous membrane : its name expresses its attachments, viz. palato- 
pharyngeus. 

The muscles here described are the principal agents in deglutition, or swallowing. When a portion of food lias been reduced 
to a pulp, it is collected into a mass upon the surface of the tongue, the tip or point of which is (see plate V. fig. 2) raised to the 
roof of the mouth, and then, by a succession of efforts, each part of its surface is .pressed upwards against the palate, by which 
means the food is forced from before backwards, having no other way to escape. In its progress it comes into contact with the 
depending soft palate, and raises it up, so as to bring it into the horizontal position on a level with the roof of the mouth, or hard 
palate ; when thus placed the soft palate forms a valve which prevents the mass of food from being pushed up towards the nasal 
cavities, and as it has the power of contraction within itself, its muscles, particularly the palato-pharyngeal, may even assist in 
propelling the mass downwards. In swallowing, we are always conscious of a preparatory movement; the mouth is closed by 
the apposition of the jaws, immediately after which the pharynx is drawn upwards. But this is not the only change which it 
sustains ; it is shortened and widened at the same time. The increase of its breadth from side to side, is effected by the stylo- 
pharyngei muscles. These, from their points of attachment, are evidently elevators of the pharynx ; but the direction of their 
fibres just as clearly shows, that as they draw it up they will stretch its sides apart, or in other words widen it, for their points 
of origin at the styloid processes are farther asunder than their insertions into the sides of the pharynx. Now during this ascent, 
the tongue-bone and the larynx ascend also ; and at the same time are drawn a little forwards, carrying with them the fore part 
of the pharynx, by which means this tube is prepared for receiving the mass of food which is pressed backwards into it, by the 
action of the tongue already noticed. As soon as it receives the morsel of food, these muscular efforts cease, the tube descends 
to its previous position, the fibres of the constrictors begin to act and compress the mass which they surround, forcing it from 
above downwards into the oesophagus ; the upper part of this latter tube being dilated, its circular fibres are stimulated to con- 
tract, so as to press the mass onwards in its course, until by a succession of such muscular efforts it is finally conveyed into the 
stomach. A slight consideration of this mechanism will enable us readily to understand how a mass of food can be made to 
ascend contrary to its gravity in animals, which feed with their heads to the ground, and how it is kept still in its globular form 
throughout its passage. The muscular fibres which correspond with its middle, or projecting points, are relaxed, those above it 
and those below it being in action, so as to keep it for a moment confined; — then the lower fibres are made gradually to give 
way, as if overcome by the action of the superior ones, and as they relax they will come into apposition with the most projecting 
part of the mass — that degree of contraction which is necessary for its support and confinement being taken on by the fibres still 
lower clown, so that a state of contraction and relaxation being assumed successively by a series of circular fibres placed along 
the whole length of the tube, they will sustain and propel its contents, at the same time that they limit the rapidity of its pass;i 
and impress upon it the globular form. Fluids whilst being swallowed are controlled by the same agency; they do not trickle 
along the canal or run in a stream. In animals which drink with their heads downwards, we see that each portion of fluid which 
is taken up by the mouth is made to pass along the oesophagus in a globular form, as if it were solid ; for the contractile fibres 
which surround the tube apply themselves to the surface of the fluid so as to grasp it at all points, and retain it in that form : 
and such is the consent and harmony between them, that they can give way and contract by so nice an adjustment, thai they 
will convey it to its destination in the same form as they received it. It is by calling these muscular powers into action, th 
mountebank is enabled to swallow fluids when standing on his head. We have spoken here of the oesophagus and pharynx as 
being the agents of deglutition ; they differ much, however, not merely in form, but in structure ; that of the oesophagus being 
more simple and uniform, as its muscular structure consists of fibres disposed, some in the longitudinal, and others in a circular 



14 

direction ; but in the pharynx they are arranged, as we have seen, in a very different manner, and arc also more highly deve 
loped, which renders it probable, that this part of the canal performs some other functions besides that of receiving and pro- 
pelling such lubstances as ue to be conveyed into the stomach. It appears to exert an important influence in the modulation 
of the voice, more particularly in the production of its higher notes ; for if the fore-finger and the thumb be placed at the opposite 1 
sides of the throat, so as to embrace the tube of the pharynx, and if, at the same time, an effort be made to produce the different 
notes of the musical scale in the ascending order from the lowest to the highest, it will be found that the sides of the tube, which 
are at first soft and relaxed, gradually become tense, and finally rigid, when the higher notes are produced. 



PLATE VI. 

We have here several drawings of the muscles which move the globe of the eye, intended to illustrate their relative posi- 
tions, their points of attachment, and actions. In fig. 1, the globe of the eye with its muscles is seen from the side, and it is 
obvious that they do not fill the whole of the orbit or socket in which they are placed ; considerable space is left, which is occu- 
pied by arteries, veins, and nerves, and a large quantity of adipose substance, which fills up the interstices— the eye is thus 
supported, and as it were cushioned in its natural position, admitting of rotation upon its axis, and of being directed to every 
point in the field of view which lies before it. The muscles are closely collected together at the back part of the orbit where it 
is very narrow ; they spread apart from one another where they embrace the globe of the eye, and are inserted into its outer coat 
or membrane. It will be observed that there are seven in all : one however belongs to the upper eye-lid, (fig. 1, 2, No. 1,) the 
rest appertain solely to the globe of the eye. § Four of these are called straight muscles, from their direction, (fig. 2, No. 4, 5, 6, 
7,) and two are oblique, (fig. 2, No. 2, 8.) The four straight muscles are attached behind to the sphenoid bone, round the aper- 
ture which transmits the optic nerve ; their opposite ends are inserted into the outer membrane of the globe of the eye, at opposite 
points of its circumference, as may be seen in. fig. 4, one lying above it, another beneath it, and one on each side. 

In fig. 1, the muscles which move the globe of the eye are seen in their natural position whilst kept enclosed within the 
orbit, the outer half of which is cut away. In fig. 2, the muscles and the eye are more distinctly seen, for no part of the osseous 

PLATE VI. 

The muscles which move the globe of tin- eye. 

Fio. 1, is a vertical section of the orbit at the right side, the muscles and the globe of the eye being left in their natural positions. No. 1. The 
elevator muscle of the upper eyelid, (m. levator palpebrae superioris; m. releveur de la paupiere superieure.) 2. The superior oblique 
muscle, running through its pulley and reflected (3) backwards and outwards to the globe of the eye, (m. obliquus superior, trochlearis; 
m. grand oblique.) 1. The superior straight muscle, (m. rectus superior; m. droit superieur.) 5. Part of the internal straight muscle; 
(m. rectus interims.) G. The external straight muscle, (m. rectus externus.) 7. The lower straight muscle, (m. rectus inferior.) 8. 
The inferior oblique muscle, (m. obliquus inferior.) 9. The optic nerve at its entrance into the orbit. 

Fig. 2. The same structures as in the preceding, detached from their connexions with the orbit, so as to be more distinctly seen. No. 1. 
The elevator of the upper eyelid. 2. The superior oblique muscle with its pulley. 3. Its reflected tendon. 4. The superior straight 
muscle. 5. The internal straight muscle, partly concealed by the optic nerve. G. The external straight muscle ; its origin and inser- 
tion are retained, but the middle part is cut away to show the position of the optic nerve. 7. The inferior straight muscle. 8. The 
inferior oblique muscle. 9. A small piece of the superior maxillary bone from which it arises. 

Fig. 3. The globe of the eye and its muscles seen from behind. No. 1. The optic nerve cut across. 2. The superior oblique muscle. 
3. A sheath of synovial membrane which surrounds it as it passes through its pulley to facilitate its movements. 4. The superior 
straight muscle. 5. The internal straight muscle. G. The external straight muscle. 7. The inferior straight muscle. 8. The infe- 
rior oblique muscle. 9. A small piece of the bone from which it arises. 

Fig. 4. The same parts viewed in front, the straight muscles being drawn out of their natural position, in order to show their insertion at 
the fore part of the globe of the eye, at opposite points. No. 1. The superior oblique muscle, its pulley and a part of the frontal bone 
(2) to which it is attached. 3. The superior straight muscles. 4, 5, 7. The. other three straight muscles. 8. The inferior oblique 
muscles. 9. The part of the bone from which it arises. 

Fig. 5. The elevator muscle of the upper eyelid seen by itself. It arises by a pointed process at the back part of the roof of the orbit a 
little above the aperture which transmits the optic nerve: it widens (4) as it passes forward over the globe of the eye, and is inserted 
into the cartilage (5) of the upper eyelid. G. The eye-lashes. 

Fig. G. Exhibits the two oblique muscles of the eye-ball in their natural position when viewed from before, and also some small muscles 
of the face which were not shown in the previous drawings. No. I, 2. The superior oblique muscle of the eye running through its 
pulley. 4. The inferior oblique muscle, its direction being backwards and outwards to the globe of the eye from near the lower 
margin of the orbit. 5. The elevator muscle of the upper lip. G. Part of the orbicular muscle of the lips. 7. The depressor muscle 
of the \s ing of the nose. 8, 8. The elevator muscles of the lower lip 



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15 

structure is retained, except a small piece of the sphenoid bone, near the entrance of the optic nerve. One of those here seen, 
and which is drawn separately in fig. 5, acts upon the upper eye-lid, and raises it, so as to uncover the front of the eye ; it is 
therefore called the elevator of the lid, and is the antagonist of the orbicular muscle, which closes the eye-lids; it is marked 1, 
figs. 1, 2. The four straight muscles are composed of fleshy fibres in the greater part of their extent; but opposite the middle 
of the globe of the eye, they end in thin tendons which are fixed into the sclerotic coat, about two lines and a half behind the 
margin of the cornea and at opposite points, as may be seen in fig. 4. These muscles are under the control of the will— they 
receive their nervous influence from the third cerebral nerve.* As their points of insertion are anterior to the transverse diameter 
of the globe of the eye, and as each, before it reaches its point of insertion, curves over the rounded surface of the eye, it requires 
but little consideration to perceive that, when in action, their effect must be to turn or rotate the ball of the eye, as it were upon 
an axis — the superior one will turn the transparent part of the eye, and with it the aperture of the pupil upwards, the inferior 
one downwards ; that which lies to the external side, will incline it outwards as in lateral vision, and that at the opposite side 
will turn it inwards ; the effect of this will be rendered more apparent if a needle be passed through the transparent cornea, and 
the upper and lower muscle be alternately pulled, either with the fingers, or a pair of forceps. If two of the straight muscles act 
together, for instance, the superior and the external one, the pupil will not be turned directly upwards or outwards, but to the 
point intermediate between these, viz. upwards and outwards. In the same way, the combined actions of the internal and infe- 
rior straight muscles will turn it downwards and inwards. By this succession, combination, and alternation of action of the four 
straight muscles, we are enabled to direct the transparent part of the eye, and the pupil, with the most minute precision to every 
point within our field of view, so as to receive the rays of light reflected from them upon the most sentient part of the retina. 

These muscles are in absolute dependence upon the will. There also subsists between them and the retina a close sympathy ; 
for when the nerve is paralysed as in amaurosis, so that it is no longer capable of being influenced by its appropriate stimulus, 
those transversing motions cease by which it is directed to the different objects within its field of vision, and it loses that peculiar 
expression which is indicative of watchfulness and intelligence. The oblique differ from the straight muscles in several particu- 
lars. They are inserted into the ball of the eye, behind its middle part ; the direction of the inferior one is backwards and 
outwards, its fixed point being near the anterior margin of the orbit. The superior oblique muscle commences at the back part 
of the qrbit near the origin of the straight muscles, but it passes through a cartilaginous ring or pulley attached to the upper 
margin of the orbit, by which it changes its direction, and runs backwards and outwards, to reach the back part of the ball of. 
the eye, into which it is inserted about three or four lines from the entrance of the optic nerve. Both the oblique muscles may 
therefore be said to act upon the eye from the fore part of the orbit, as the recti do from the back part. On this was founded the 
opinion once entertained, that one set were the antagonists of the other — the straight muscles when in action tending to draw the 
eye back into the orbit, and the oblique preventing the retraction going too far. But this opinion is no longer tenable : we know 
that in quadrupeds, besides the straight muscles, a retractor muscle of great power is fixed to the back of the eye, yet the oblique 
muscles are not more strongly developed in these creatures than those that have got no retractor; and they exist in others where 
••etraction cannot take place ; inasmuch as the eye is supported not by adipose substance, but by cartilage. From what we have 
above observed concerning the powers of the straight muscles, it might be thought that all the necessary movements of the eye 
were provided for, and effected by them alone ; but merely to move and direct the organ is not sufficient, — a provision is required 
to secure it from the injurious influences to which it is exposed. When any irritating particles come into contact with the eye, 
the lids are made to close, not merely to exclude these, but as it were to brush or wash them off; but this of itself would not 
suffice, if the eye-ball were motionless. In order to be effectual, the latter must be made to revolve and turn upwards as the lid 
descends, so that they shall move one upon another in opposite directions; and this is what invariably takes place in all winking, 
involuntary, or spasmodic motions ; in these cases the straight muscles, which are the voluntary powers, cease to exercise any 
control, and the oblique muscles assume the direction and turn the organ upwards. It is matter of observation, that those muscles 
which are strictly voluntary, and which under ordinary circumstances are most readily controlled by the will, lose their power 
the soonest when the cerebral influence upon them is weakened or impaired. We may perceive this, says Sir C. Bell, " in the 
progressive stages of debility in the drunkard, when successively the muscles of the tongue, of the eyes, the face, and the limbs, 
become unmanageable ; and under the same circumstances, the muscles which have a double office, as those of the chest, lose 
their voluntary motions, and retain their involuntary motions." In the case Avhich we are now considering, the straight muscles 
being voluntary, lose their power before the oblique muscles, so that the latter, assuming the sole direction of the organ, roll it 
upon its axis, and place the transparent part of the eye under cover of the lid ; the white or opaque part alone appearing in the 

* The third pair of nerves (motor communis) supplies three of the straight muscles only; the rectus externus receiving a distinct nerve, called tin sixth, 
(motor externus.) Each of the recti muscles is inserted upon the sclerotica, not by a point, but by a slip of tendon 8-20 to 7-20 of an inch broad. The fibres of the 
muscles which are attached to the lateral margins of the tendon, must therefore, where they act separately, incline the ball slightly in the same direction. The 
three recti which are supplied by the third pair of nerves, when they act together under the stimulus of that nerve, will have a tendency to sink tin- boll of die 
eye somewhat, and turn the cornea towards the inner canthus, as we find it in strabismus convergens. Here we find one of the probable causes that maki 
internal form of strabismus of so much more frequent occurrence than the external. It is well to observe, too, that the same third pair which supplies ll 
muscles, sends a branch through the ophthalmic ganglion, which is believed to be the nerve of motion to the iris. J- !'• 



16 

interval between the lids, if they are partially open. This is the state in which the organ is found in the quiescence of sleep, or 
in the insensibility which precedes the approach of death. By means of the great variety and freedom of motion given to tlic 
. to which its globular form contributes not a little, and for which there is such ample provision in the number of its muscles, 
it is rendered capable of being an agent in the expression of desires and wants, as well as of passions and feelings. A movement 
of the eye accompanies that of the hand, when raised to supplicate or denounce, and in each case it assumes an appropriate 
expression. In persons born dumb, the eye is so constantly made the outward index of their feelings, that they become in a 
manner concentrated to it, giving it a character and a brilliancy quite peculiar. Do we not see the eye at one time tremblingly 
agitated in violent passion, then softened into pity, or glancing with anger or disdain? As these states are capable of being 
controlled by an effort of the will, so they admit of being simulated— the skilful actor can put them on with the characters he 
assumes, and delineate their workings, as if they were prompted by real passion.* 



PLATE VII. 

The first and second figures represent the pterygoid muscles which are principal agents in the movements of the lower jaw. 
The articulation of the lower jaw with the base of the skull is so constructed as to allow not only the hinge-like movement by 
which the mouth is alternately opened and shut, but also a lateral or horizontal motion, by which the lower teeth are made to 
rub across those of the upper jaw, in order to crush and triturate the food. The jaw may be depressed, so as to open the mouth 
slightly, by the relaxation of its elevator muscles, but it is drawn down so as to dilate the aperture fully by the action of those 
muscles which proceed upwards to it from the tongue-bone ; and it is drawn up so as to close the mouth by means of the masseter 
and the temporal muscles which are seen in plate VIII., and the internal pterygoid which is shown in plate VII., fig. 1, 2, No. 9. 
In carnivorous animals these muscles exhibit their maximum of developement. In these creatures, the teeth, instead of flat 
crowns, present sharp cutting edges, and the movement of the lower jaw upon the upper is somewhat like that of the blades of 
a pair of scissors. The zygoma is strong, and inclines upwards so as to give additional power to the masseter muscle, and it 
moreover arches forward considerably, to accommodate itself to the great mass of the temporal muscle which lies behind it. This 
conformation is seen at its maximum in the head of the lion and tiger ; but in the human subject the zygoma is thin, small, 
and very slightly arched. On referring to plate VII., it will be seen that the lower jaw represents a lever of the third order, the 
fulcrum being at one end, viz. in the socket, (No. 5,) the resistance being at the other, and constituted by whatever is placed 
between the teeth to be cut or crushed, whilst the moving power, at least in the elevation of the jaw, is between these, viz. the 
internal pterygoid muscle No. 9, as seen in plate VII., and the masseter as seen in plate X.,fig. 1, 19. It is not a little remarkable 
that this is the mechanical contrivance most commonly employed in the living fabric ; it is necessarily accompanied by a loss of 
power, for which, however, there is ample compensation in the velocity of movement which is acquired. The direct elevation 
of the lower jaw is effected by the temporal muscle ; the masseter and the internal pterygoid are also powerful agents in effecting 
this end. The obliquity of the anterior fibres of the two latter enables them also to draw the angle of the jaw somewhat 
forwards ; and the posterior fibres of the temporal muscle run so obliquely downwards and forwards to their insertion into the 
coronoid process, that they seem calculated not only to elevate the jaw-bone, but also to draw it backwards ; but in continued 
and strong efforts, for instance, when we seek to support or draw up anything by catching it between the teeth, the different lines 
of direction here indicated are discomposed, when the muscles all act together, and the jaw is drawn directly upwards. 

* The doctrine that the oblique muscles of the eyes are provided for the purpose of drawing the ball forwards, and opposing the retractive action of the recti, 
i* as old as the time of Boerhaave, and has still many supporters. It is, however, without foundation ; and besides the reasons alleged against it above.it may be 
added among others, that in many animals, as the sheep and the horse, the oblique, if they act in either way upon the ball, must draw it backward, for the trochlea 
of the superior and the origin of the inferior oblique are much posterior to the insertion of their tendons upon the sclerotic ccat. Since the operation for strabismus, by 
dividing the tendon of one of the muscles of the eye, has become so common, and found so generally successful when judiciously performed, it is a matter of 
considerable interest to ascertain the exact office of the oblique muscles, which are found so uniformly existing in the various classes of animals. It has not yet 
been satisfactorily done. In the course of about one hundred and thirty operations for this affection 1 have several times divided both the oblique muscles. But 
in no instances were the voluntary movements or the position of the ball apparently affected by their section. In two cases, where there was presbyopia, or 
farsightedness, the division of the obliques was attended with a manifest improvement in vision. In one strongly marked case, that of Mr. Jacob Phillips, of this 
city, <et. twenty-one, so presbyopic as to require the constant use of glasses suited to persons of sixty or seventy years of age, the operation practised for the 
purpose almost immediately restored the eyes to the degree of vision usual at his age ; and the improvement has been permanent. On the same individual I had 
previously divided, without the least remaining deformity, the two internal recti for double strabismus. It appears to me that the oblique muscles, besides the 
offices mentioned in the text, rotate the ball on its axis from side to side, and very possibly, by acting in combination with the recti, so modify its shape as to 
aid the eye in accommodating itself to vision at different distances. Vide a paper on vision by Dr. D. Hosack, Lond. Philos. Trans. 1794. Each of the 
obliques, I have found by experiments upon the dead body, is capable of giving the ball a quarter rotation, the one antagonising the other, and moving the 
organ upon a middle oblique axis, which from the external border of the cornea runs obliquely backwards and inwards. The great oblique by an internal 
rotation carries the pupil downwards and outwards; the inferior oblique by an external rotation of the ball carries the pupil upwards and outwards. — J. P. 



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17 

We can readily push the lower jaw forwards, and make the teeth project beyond the upper dental arch by means of the 
external pterygoid muscle of each side, which, when they act together, will draw the condyles directly forwards. The digastric 
muscle draws the chin backwards, and replaces the bone acting as a retractor. In plate VII., fig. 1, No. 8, the external pterygoid 
muscle of the right side is seen running backwards, and outwards, to be fixed to the neck of the lower jaw-bone and its inter- 
articular cartilage ; it obviously can pull the condyle directly forwards towards its point of fixed attachment ; and if the muscle 
of the right side acts in this way, whilst the condyle at the left side remains in its socket, the chin is made to deviate to the left 
side, and the lower teeth are rubbed horizontally across the upper ones. If this effort be discontinued, and the muscle of the 
opposite side be brought into action, the movement of the jaw is reversed, and this alternation of action by the two external 
pterygoids will produce that triturating motion by which any substance placed between the teeth is crushed or comminuted. The 
most perfect provision for this movement is made in herbivorous and ruminating animals, which are furnished with broad 
crowned teeth adapted to crush and triturate their food. 



PLATE VIII. 

The movements and actions of the muscles of the forehead, eyebrows, cheeks and mouth, of which a side-view is given in 
this plate, have been sufficiently dwelt upon in our remarks on expression, page 7; and the uses of the masseter, (fig. 1, 19,) and 
of the temporal muscle (fig. 2, No. 1,) have been stated in the observations just made on mastication. The muscles which are 
attached to the external ear have seldom any power of action in the human subject ; but in several of the lower animals they 
are highly developed and obedient to the will, which enables these creatures to turn the hollow of their ears towards that point 
from which sounds issue, or from which they apprehend danger or surprise. 



PLATE VII. 

Shows some of the muscles which move the lower jaw and the tongue. 

Fig. 1. Exhibits two of the muscles of the lower jaw, as seen from the outside, with their points of attachment. No. 1. The malar or 
cheek-bone. 2. The root of the zygomatic process, the intervening portion of the zygoma being cut away to expose the two pterygoid 
muscles. . 3. The superior maxillary bone. 4. The lower jaw-bone. 5. The inter-articular cartilage, which is placed between the 
condyle of the lower jaw, and the glenoid fossa with which it articulates. 7. The condyle. 8. The external pterygoid muscle, 
consisting of two portions, of which one is attached to the external pterygoid plate of the sphenoid bone, and to the tuberosity of the 
palate bone, and the other higher up to the lower part of the great wing of the same bone: both become narrow and unite previously 
to their insertion into the neck of the condyle of the lower jaw, and the inter-articular cartilage. 9. The internal pterygoid muscle, to 
expose which part of the branch of the lower jaw with its coronoid process has been cut away. 10. The superior portion of the 
external pterygoid muscle. 11. The inferior portion of the same muscle. 

Fig. 2. Shows the same parts when viewed from the inside. No. 1, 2. A vertical section of the sphenoid and occipital bones. 3. The 
frontal bone cut through, its sinus being laid open. 4, 4, 4. The turbinate bones of the nose. 5. The hard palate cut through. 
6. The lower jaw-bone sawed at its symphysis. 7. A small piece of the external pterygoid plate of the sphenoid bone. 8. The 
internal pterygoid plate. 9. The internal pterygoid muscle which is attached above to the groove between the pterygoid plates, and 
below to the branch, and the angle of the lower jaw. 10. Part of the external pterygoid muscle. 

Fig. 3. The tongue-bone, (os hyoides, os linguale,) its upper surface as seen from before. No. 1. The body of the bone. 2, 2. Its great 
horns or processes, (comua.) 3, 3. Its small horns or processes, (cornicula.) 

Fig. 4. A lateral view of the same bone. No. 1. Its body. 2. Its great processes. 3. Its small processes. 

Fig. 5. A lateral view of the tongue and its principal muscles. The left side of the lower jaw-bone and the tongue-bone, being retained 
in their natural positions, together with part of the temporal bone of the right side. No. 1. The lower jaw-bone. 2. Part of the 
temporal bone. 3. The styloid process. 4. The tongue-bone. 5. The mastoid process. 6. The condyle of the lower jaw. 7. Its 
coronoid process. 8. The section of the lower jaw at its symphysis. 9. The great process (comu,) of the tongue-bone. 10. Its 
small process. 11. The upper surface of the tongue. 12. The stylo-glossus muscle. 13. The stylo-hyoid muscle extending from 
the styloid process to the tongue-bone. 14. A slit in its fibres through which the tendon of the digastric muscle passes. 15. Part of 
the stylo-maxillary ligament. 16. The stylo-hyoid ligament. 17. The hyo-glossus muscle. 18. The genio-hyo-glossus muscle, iis 
name expresses its three points of attachment, viz. to the inside of the lower jaw at the chin, to the tongue-bone, and to the under 
surface of the tongue, along its entire length, from its root to its point; it is composed of diverging, or rather radiating i 
19. The genio-hyoid muscle. 

Fig. G. Another view of the same parts, — the hyo-glossus muscle being thrown down, so as to expose more fully the genio-hyi 

and the lingualis. No. 1. The mastoid process of the temporal bone. 2. The lower jaw-bone. 3. The lingualis muscle. 4. The 
tongue. 5. The stylo-glossus muscle. 6. The hyo-glossus muscle reflected downwards so as to expose (3. 7.) the lingualis and (8.) 
the genio-hyo-glossus. 9. Part of the stylo-hyoidcus muscle. 
Musci.es. — 3 



18 



PLATE IX. 

The uses of the different muscles here exhibited have been already detailed in our remarks on the movements of the jaw, 
the tongue, and the larynx, in deglutition and mastication. 

Dislocations of the lower jaw. — The different pieces which compose the skeleton, are connected one to the other in various 
ways, — no motion whatever is admitted between some, a restricted movement takes place in other cases, whilst in some a free 
motion is provided for in various directions. It often happens that the bones which form the joints, particularly in the limbs, are 
thrown by various accidents into new situations, so as to lose their natural position and relation with regard to one another ; in 
other words, they are displaced, or to use the technical phrase, dislocated. In studying the dislocations of a particular joint, it is 
usual to enquire in how many ways they may occur; and this includes a consideration of the form and mutual adaptation of the 
articulating surfaces of the bones, — of the arrangement and form of the ligaments which connect them, — the direction of the 
shafts of the hones themselves, and above all, the direction, power, and modes of action of the different muscles placed round 
the joint. Dislocation occurs much more frequently in some joints than in others, arising from the great variety and freedom of 
motion which they admit of; and also from the effects of pressure being more frequently transmitted to them: for instance, the 
shoulder-joint is so constructed, that the head of the arm-bone moves in every direction upon a small and shallow surface in the 
scapula or blade-bone, from off which it may pass in different directions with great freedom, so far as the form of the articulating 
surfaces and the structure of the ligaments are concerned ; and this natural liability to displacement is encreased by the circum- 
stance that persons instinctively throw out their hands whilst falling, in order to protect themselves, and so the pressure and the 
concussion become propagated by the bones to the shoulder-joint, and dislocation is produced. To this natural liability to such 
accidents, there is further added, in many instances, what may be termed an acquired one, owing to a laxity of the ligaments 
produced either by effusion into the joints, or by previous dislocations, and still more by weakness of the surrounding muscles, 
resulting from previous dislocations, or caused by paralysis. When such a state of muscle and ligament exists at the shoulder- 
joint, dislocation often occurs from slight causes ; and owing to a similar state of relaxation in the articulation of the lower jaw, 
dislocation has occurred in some individuals whilst yawning. The lower jaw-bone admits of three displacements : first, both its 
articulating processes are thrown forwards under the zygomatic arch ; secondly, one of them is brought forward, whilst the other 
remains in its natural state ; lastly, it may slip before the inter-articular cartilage, owing to relaxation of the ligaments. The last 
is termed subluxation of the jaw ; the first is the complete dislocation ; the second is termed partial : all, however, take place in 
one direction, viz. forwards. The head of the bone cannot go backwards, for that would require that its dental arch should 
ascend to a level above its position when the teeth are closed, which is quite impossible : it is opposed, moreover, by the osseous 
plate of the auditory tube, and is not promoted by the action of any muscle : on the contrary, it is opposed by the external 
pterygoid muscles. Displacement directly inwards is prevented by the structure of the articulating surface, and by the spine of 
the sphenoid bone : and as it could only be produced by a blow upon the cheek, a force so applied would break the bone more 
readily than it could displace its articulating extremity. Dislocation of the lower jaw cannot occur in infants for in them the 
branch of the bone forms an obtuse angle with its body, so that the neck which supports the condyle is nearly in the same 
direction as the body of the bone. While such a conformation exists, the action of elevator muscles would tend to press the bone 

PLATE VIII. 

Fig. I. Gives a side view of the muscles of the external ear, of the cranium, and of the face. 1, 1. The occipitofrontal muscle. 2. The 
fascia which hinds down the temporal muscle, and conceals it. 3. The elevator muscle of the external ear, (m. attollens aurem; m. 
aunculaire superieure.) 4. The anterior muscle of the ear, (m. attrahens aurem ; m. auriculaire anterieure.) 5. The posterior muscle 
of the ear, (m. retrahens aurem; m. auriculaire posterieure.) 6. The orbicular muscle of the eyelids. 1. The pyramidalis nasi 
muscle. 8. Part of the triangular muscle of the nose, commonly called the compressor. 9. The elevator of the lip and nose. 
10. The elevator of the upper lip. 11. The small zygomatic muscle. 12. The great zygomatic muscle. 13. The elevator muscle 
of the angle of the mouth. 14. The orbicular muscle of the lips. 15. The elevator of the lower lip. 16. The depressor of the lower 
lip. 17. The depressor of the angle of the lip. 18. The buccinator muscle. 19. The masseter muscle, its external or largo p, rtion. 
20. The smaller or deep-seated portion of the same muscle. 21. The external lateral ligament of the lower jaw-bone. 

Fig. 2. Gives a side view of the temporal muscle exposed by removing the strong membrane called the temporal fascia s< ( r, in fig. 1. No. 
2, and by removing the masseter muscle, together with the zygoma. No. 1. The temporal muscle, (m. temporalis,) which is broad 
and radiating at its upper part, and narrowed almost to a point at its lower extremity, where it is inserted into the coronoid process (-2) 
of the lower jaw-bone. 3. The external lateral ligament of the lower jaw-bone. 



Muscles 



Plate X 




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19 

clo ely to its socket rather than draw it forwards out of its place. This accident can occur only when the bone ; 
formed, and when its branch, or ascending part, forms nearly a right angle with its body, as is here delineated, (plate VIII., 
When the jaw is alternately depressed and elevated, it moves as it were upon an imaginary centre, corresponding with the middle 
of its bmnch, which is the flat square projecting upwards, nearly at a right angle with its body or horizontal part. If a pivot be 
driven through the bone at this point, it will at once be perceived on depressing the jaw, that its angle passes backwards and 
upwards, whilst its head moves downwards and forwards, describing small arcs of circles. If this motion be carried to a 
considerable extent, as in gaping, the direction of the masseter muscle, (plate VIII., fig. 1, No. 19,) is rendered more oblique than 
in the natural state, so is the internal pterygoid muscle, and the masseter will be observed under such circumstances to be 
stretched downwards and backwards towards the angle of the jaw. Now, if in such a state of things, a slight blow be given to 
the jaw, the muscles may be made to contract suddenly, and concentrating their force upon the angles of the bone, they are enabled 
to draw them forwards, and thereby press the condyles under the arch of the zygoma. It is very likely that the depressor muscles 
at the same time give a certain degree of fixity to the chin ; and also that the external pterygoid muscles draw the condyles for- 
wards, thus contributing to produce the displacement. When this accident occurs, the appearance of the patient is that of forced 
and continued yawning ; the mouth gapes, the cheeks and temples are flattened, for the masseter, the temporal, and buccal muscles 
are lengthened, and in a state of tension ; the external pterygoid muscles are relaxed. The elevator muscles are the antagonists 
which oppose our efforts to replace the bone in its natural position. To overcome their resistance, the surgeon avails himself of 
an expedient, which enables him to act on the jaw itself, as if it were a lever of the first order ; and it can be rendered such by 
placing a fulcrum, or prop, at each side, behind the last grinder teeth, at the angle formed by the body and the branch of the 
bone ; and a piece of firm cork will suffice for this purpose. If the patient be placed in the horizontal position, with his head 
supported on a pillow, and the corks are inserted between the jaws as just stated, by placing the hand under the chin, and drawing 
it steadily upwards, the angles of the bone will be pressed backwards and downwards, the muscles will be kept still more on the 
stretch, fatigue will be induced in them, and their resistance will gradually cease, and the bone will pass backwards into its place. 
Some of the fibres of the opposing muscles may assist in promoting this end ; for those which form the lower part of the temporal 
muscle, (plate VIII. fig. 2, No. 1,) by reason of their direction, are enabled to draw the coronoid process of the bone backwards, 
and some of the deep-seated fibres of the masseter can give the branch of the bone a similar direction. When the power is 
applied in the way above directed, to the chin or front of the bone, the resistance is at the opposite end, and the fulcrum between 
both ; the process of reduction becomes a mechanical contrivance by which we convert the jaw into a lever of the first order. 

Partial dislocation of the jaw consists in the displacement of one of its condyles, which is drawn forwards under the zygo- 
matic arch, whilst the other remains in its place. The chin, in such accidents, necessarily deviates to the side opposite to that in 
which the dislocation has occurred ; so does the dental arch of the lower jaw, which also protrudes beyond that of the upper one. 
The mode of reduction is the same in this case as when the dislocation is complete, save only that one fulcrum placed between 
the jaws will suffice. 

The subluxation of the jaw arises from relaxation of the ligaments, and consists of a displacement of the condyle from its 
inter-articular cartilage, by which the jaw becomes motionless for a time, the mouth being kept slightly opened. Surgical assist 
ance is seldom required in such cases, as the patient's muscular efforts alone generally succeed in righting the displacement. 



PLATE X. 

We have here given Cloquet's dissection of the pectoral muscles, with part of the deltoid and of the biceps. The insertion 
of the pectoral muscle into the humerus not being perceptible in fig. 1, it is shown in fig. 2, No. 6, where it appears in the form 
of a flat tendon, doubled on itself previously to its insertion into the anterior border of the groove which lodges the long tendon 
oi the biceps muscle. The great pectoral muscle, fig. 1, No. 8, consists of fleshy fibres in the greater part of its extent; its inser- 
tion is tendinous, its points of attachment along the sternum are aponeurotic, and along the clavicle it is slightly aponeurotic. It 
reaches from the last-named bone down to the cartilage of the seventh rib, along which it arises by an oblique border. The 
middle fibres of the muscle extend transversely outwards ; those which come from the clavicle descend, whilst the inferior fibres 
ascend, and as they pass to their insertion they lie posterior to the others; by this arrangement they become folded along the 
anterior margin of the axilla. This muscle is subjacent to the skin and superficial fascia, the mamma alone interposing towards 
its middle, and some fibres of the platysma myoides towards its upper part. The deltoid muscle, fig. 1, No. 9, forms a fleshy 
cap, which covers the shoulder-joint; its fibres are arranged into thick and coarse bundles; it overlays the tendinous insertion of 
the pectoral muscle, and conceals those different structures Avhich lie around the joint, and which can be exposed only by its 
removal, as is seen in fig. 2. When the pectoral muscle is brought into action, it draws the shaft of the humerus inwards to the 
side, and then forwards upon the chest if its efforts be continued. If the arm be previously everted, this muscle, by its mode of 



20 

insertion, is enabled to assist in rotating it inwards ; and when the arm is elevated into the vertical direction, the lower or ascend- 
in '_' fibres of the pectoral muscle will draw it downwards. If the humerus be fixed, then this muscle can be made to reverse its 
mode of action, so as to draw upon the chest, by taking its fixed point upon the arm. Thus when, by elevating his arms, an 
individual catches an object placed above him, and seeks to elevate his body as in climbing, the pectoral muscles will combine 
with others, to draw the body upwards. This power of acting on the chest when the arms are fixed, enables it to dilate the walls 
of the cavity in the efforts of forced inspiration. When the arm of a crutch is placed under the axilla, and the lower margin of 
the pectoral and latissimus, fig. 1. 12, are made to rest upon it, these muscles, by taking their fixed points at the humerus, which 
is rendered steady as soon as the hand grasps the crutch, will act upon the chest, and pull it upwards towards the fulcrum upon 
which they rest. In this way the body is lifted and supported, at the same time a slight effort sufficing to carry the legs onwards 
in progression. 

The deltoid muscle draws the arm outwards from the side, so as to bring it into the horizontal position, and by a continuance 
of its effort it can lift the arm upwards nearly into the vertical direction. When the arm is thrown outwards from the side, the 
anterior fibres of the deltoid can assist the pectoral muscle in drawing it forwards towards the chest, and the posterior fibres, 
(which, however, are not seen in this drawing, as they come from the spine of the scapula,) can move it backwards. 

Fig. 2. exhibits the subclavius muscle, 7, and the small pectoral muscle, 9, in such a way as to render their actions readily 
intelligible. The subclavius is a long and narrow muscle, stretched obliquely from the cartilage of the first rib outwards, to be 
fixed to the under surface of the clavicle. When in action, it will depress the clavicle, and assist in drawing it forwards; but if 
the shoulder is fixed, then it will act on the first rib and steady it, assisting thereby to make it the point towards which the other 
ribs are drawn in inspiration. 

The small pectoral muscle, 9, extends obliquely upwards and outwards, to be fixed to the coracoid process of the scapula. 
It therefore crosses the axilla and axillary vessels, and when the parts are in their natural position it is covered by the great 
pectoral muscle. It was sometimes called the small anterior serrate muscle, in consequence of its attachment to the ribs by angular 
processes. When in action, it can draw the coracoid process downwards and forwards, giving thereby a similar inclination to 
the shoulder-joint ; in which movement the inferior angle of the scapula is made to move backwards and a little upwards. If, 
however, the lower part of the serratus magnus is in action at the same time, the shoulder is made to come directly forwards. 
This muscle can assist in dilating the chest, for if the shoulder be previously fixed, it will act from the coracoid process and draw 
upon the ribs to which it is attached. 

PLATE IX. 

The second layer of muscles placed at the front of the neck is here shown in the position in which they are ordinarily seen during dissec- 
tion, when the middle of the neck is supported by a block, and the head is extended backwards. The sterno-mastoid and the platysma 
muscles are taken away, together with the cervical fascia. 

No. 1. The lower jaw-bone. 2, 2. The mastoid processes of the temporal bone at each side. 3, 3. The clavicles. 4. The under surface 
of the acromion process of the scapula. 5. The extremity of the coracoid process. 6. The glenoid or articulating cavity of the 
scapula. 7. The first bone of the sternum. 8, 9, 10. The three upper ribs. 11. The digastric muscle. 12. The stylo-hyoid muscle. 
13. The mylo-hyoid muscle of the left side, which is attached to 14, The tongue-bone. 15. The oblique fibres of the muscle just 
named, inclining inwards to meet those of it fellow of the opposite side, which, however, is here taken away to expose the two 
following muscles, viz. 16, The genio-hyoideus, and 17, The hyo-glossus. 18. The stemo-hyoideus muscle. 19. The sterno-thyroideus 
muscle of the right side, partly covered by the preceding muscle. 20. The stemo-thyroid muscle of the left side, which is here 
exposed by removing the stemo-hyoideus. 21. The thyroid cartilage. 22. The thyro-hyoideus muscle, which is continued upwards 
from the oblique line into which the stemo-thyroid is inserted almost as if it were a prolongation of it. 23. The omo-hyoideus muscle, 
seen in its entire length. The upper part lies parallel, and on the same plane with the stemo-hyoideus muscle, whilst the lower part 
extends downwards and backwards to the upper border of the scapula, into which its fibres are fixed as well as into the ligament (24) 
which crosses the supra-scapula notch. 25. The anterior scalenus muscle. 26. Tire posterior scalenus muscle. 27. The rectus 
amicus major muscle. 28. Part of the levator anguli scapulae muscle. 29. Part of the splenius muscle. 30. The membrane (thyro- 
hyoid) which connects the thyroid cartilage with the tongue-bone. 31. The membrane (crico-thyroid) which connects the criwid 
with the thyroid cartilage. 32. The first ring of the wind-pipe. 33. The cricoid cartilage. 34. The thyroid gland. 35. The rings 
of the wind-pipe. 36. The upper intercostal spaces. 

Fig. 2. The first bone of the sternum is here seen detached in order to show the points of origin of the stemo-hyoid and stemo-thyrcid 
muscles, which can only be seen in part, as in fig. 1,-18, 20, so long as the sternum is in its natural position. 1. The posterior surface 
of the first bone of the sternum. 2, 2. Parts of the clavicles. 4, 4. The cartilage of the first rib at each side. 5. The stemo-thyroid 
muscle. 6. Part of the left stemo-hyoid muscle. 7. The right stemo-hyoid muscle. 

Fig. 3. This gives a side view of the thyroid cartilage and the hyoid bone, together with the membrane and the muscle which connect them. 
1. The hyoid, or tongue-bone. 2, 2. Its small horns or processes. 3. The large horns. 4. The thyro-hyoid membrane. 5. The 
thvro-hyoid hVamem. 6. The thyroid cartilage. 7. Its upper comu, or process. 8. Its lower eornu, or process. 9. The oblique 
ridge on the side of the thyroid cartilage, which gives insertion to, 10, The sterno-thyroid muscle, and origin to, 1 1, The thyro-hy< id 
muscle. Behind these is a part of the inferior constrictor muscle of the pharynx, spread out from its attachment to the side of the 
thyroid cartilage. 



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PLATE XI. 

We have here some muscles shown in connexion with the chest and shoulder, which are still more deeply seated than those 
seen in the previous drawings. Along the side of the chest, and resting upon the ribs and intercostal spaces, is a muscle of con- 
siderable extent, (25,) which reaches from the first, but sometimes from the second rib, as far down as to the ninth. To expose 
it, the clavicle is sawed through, and the shoulder, with the scapula, drawn backwards. It is attached to the ribs by nine angular 
points, like the teeth of a saw, from which circumstance it has been called " serratus ;" the other ends of its fibres are fixed along 
the posterior border of the scapula, a considerable number of them being concentrated towards its inferior angle. When in 
action, it draws the scapula forwards, and at the same time, by a slight effort, it can elevate the point of the shoulder, for it gives 
the scapula a rotatory motion, by means of which, whenever its inferior angle is drawn forwards, the glenoid cavity is necessarily 
turned a little upwards, and with it the' shoulder-joint. It is in this way that the serratus contributes to support the shoulder 
when a heavy burden is placed upon it. In every effort which we make when pushing anything forwards, this muscle is neces- 
sarily in action in order to fix the scapula, and make it a steady support for the humerus. When such efforts as these are about 
to be made, the ribs must be rendered immoveable by a preparatory adjustment, in order that the muscle may have fixed points, 
from which to act along the side of the chest. This can be done by taking a full inspiration so as to distend the chest, after which 
the lower border of the cavity is kept fixed by the abdominal muscles and the diaphragm, and the air is prevented from escaping 
by the closing of the chink in the larynx. The necessity of this preparatory effort is rendered apparent in persons who have a 
fistulous opening in the wind-pipe, which allows the air to escape, for they cannot fix the chest so long as the aperture remains 
open. M. Bourdon some time since ascertained the fact to be as here stated, by direct experiment. He made an opening into 
the wind-pipe of a dog that was accustomed to jump and tumble about when bidden; after the operation the animal was no 



PLATE X. 

This plate commences the delineation of the muscles which move the upper extremity. 

Fig. 1. Shows the great pectoral muscle, which is extended outwards to the arm from the breast-bone, and the cartilages of the ribs; also 
a part of the deltoid muscle, which lies over the point of the shoulder. No. 1. The right clavicle. 2. The acromion process of the 
scapula. 3. Part of the left clavicle. 4. The sternum or breast-bone. 5. Its cartilaginous appendage, (called, from its shape, xiphoid 
or ensiform.) 6. The cartilages of the true-ribs. 7. The cartilage of the seventh rib of the right side. 8. The great pectoral muscle 
(m. pectoralis major; le grand pectoral.) 9. The anterior part of the deltoid muscle, which is broad above at its attachment to the 
clavicle, to the acromion and the spine of the scapula, and narrow at its insertion into the humerus, giving it a triangular form, not 
unlike that of the Greek letter Delta, from which circumstance its name is taken. 10. Part of the subclavius muscle; placed deeply 
under cover of the clavicle, but perceptible in the interval between the two preceding. 11. Part of the small pectoral muscle, which 
is also deeply seated. 12. Part of the great muscle of the back (latissimus dorsi,) which is here seen forming the posterior fold of 
arm-pit; the lower margin of the great pectoral muscle forms the anterior one. 13. Some fibres of the great serratus muscle, seen in 
the interval between 12 and 8. 14, 15. The fleshy part of the biceps, or two-headed flexor muscle of the arm. 10. The origin of 
the anterior brachial muscle, just below the insertion of the deltoid. 
Fig. 2. Shows the parts which are seen after the removal of the pectoral and deltoid muscles. 1 . The sternum. 2. The right clavicle. 
3. The acromion process. 4. The capsular ligament of the shoulder-joint, covering the head of the humerus. 5. Part of the fibres 
of the great pectoral muscle, left at their connexion with the sternum. 6. The external part of the same muscle, which becomes flat 
and tendinous at its insertion into the humerus. 7. The subclavian muscle, lying along beneath the clavicle, to the under surface of 
which it is attached ; its inner extremity is fixed to the cartilage of the first rib, (8.) 9. The small pectoral muscle, (m. pectoralis 
minor; petit pectoral,) which is attached by separate processes to the third, fourth, and fifth ribs, from which its fibres pass upwards 
and outwards, to be inserted into the coracoid process of the scapula (10.) 11. The triangular ligament stretched from the coracoid tc 
the acromion process, so as to overhang the shoulder-joint. 12. The coracobrachial muscle, (m. eoraoo-brachialisO Its name expn 98es 
its points of attachment to the coracoid process and the humerus. 13. The inner, or short head of the biceps muscle, which is attached 
above to the coracoid process Conjointly with the preceding muscle, in apposition with which it descends along the fore part I 
humerus. 1 1. The external, or long head of the biceps muscle, seen after it has emerged from under cover of the caDSul ir ligament 
of the shoulder-joint ; the upper part of the tendon runs over the articulating head of the humerus, and is fixed - noid 

cavity of the scapula. As it runs through the joint it is surrounded by a tubular process of its synovial or lining m< mbrane. S,, 
of the fibres of the capsular ligament are here shown arching across the groove in the bone which lodges the tendon, so as to allow it 
to pass down freely. 15. The fleshy body of the muscle placed at the fore part of the upper arm. where it makes a considerable pro- 
jection. 1G. Some fibres of the anterior brachial muscle. 17. Part of the subscapular muscle, lying deep in the ax.ll:,. 18. 
of the great teres muscle, lying below the preceding. 20. The external intercostal muscles, placed between the ribs. 91. Part of 



the internal intercostal muscles, 



22 

longer able to make any similar effort, though evidently willing to do so; but when the wound was closed the lost power was 
immediately restored. The serratus muscle can, like most others, reverse its line of action; instead of acting as it ordinarily 
does upon the scapula, it can readily be made, if this bone be fixed, to act on the ribs, and draw them upwards and outwards, 
by which means it becomes a powerful agent in forcible inspiration. 

The subscapular muscle, (24,) acts upon the humerus, and makes it turn upon its own axis, rotating it inwards. It assists 
in drawing the arm towards the side if it has been previously thrown outwards, and also contributes to keep the head of the bone 
in close apposition with the surface of the shallow cavity with which it articulates. 

The scalenus anticus, (22,) can slightly bend the vertebral column laterally, and if the two muscles of opposite sides act 
together, they will contribute to maintain it in the erect position. If the neck be fixed, these muscles, acting from above, will 
draw on the first ribs, so as to fix them, and make them the point towards which the other ribs will move in inspiration. 

The posterior scalenus, (21,) exerts the same influence upon the vertebrae and ribs, which the anterior one does. The elevator 
of the angle of the scapula, (No. 20,) draws upwards the superior angle of the scapula, particularly if it has been previously 
depressed ; by this movement the glenoid cavity and the shoulder are inclined downwards. When the shoulder and scapula are 
fixed, it can act on the cervical vertebras, and draw the spine towards the side. 

Dislocations of the Clavicle.— The clavicle is more frequently the subject of fracture than of dislocation. Boyer says these 
accidents occur in the proportion of six to one. Yet were we to look at the structure of the sternal or acromial articulations of 
the bone, we should at first be disposed to think that dislocations frequently occur in them. The inner extremity of the clavicle 
rests upon a shallow notch in the upper angle of the sternum, beyond which it projects considerably, and the external extremity 
is connected with the acromion by a narrow plane surface, both conditions being apparently favourable to dislocation. The 
comparative infrequency of the accident is owing not merely to the ligaments which.form the joints just named, but also to the 
accessory ligaments which connect the clavicle with the coracoid process (coraco-clavicular) and with the first rib, (costo-clavicu- 
lar.) Moreover, in the concussion produced by a fall either on the hands or on the shoulder, a thin long bone such as the clavicle, 
will, when bent much beyond its natural curve, give way and suffer fracture towards its middle more easily than be displaced at 
either extremity. The inner end of the bone may, however, be thrown forwards upon the sternum. Dislocation downwards is 
altogether impossible, for the first rib lies beneath it ; there is no case recorded of dislocation directly upwards ; and though most 
writers admit the possibility of the displacement backwards, they do not cite any case in which it occurred as the result of violence. 
When the clavicle is dislocated forwards upon the sternum, the shoulder is depressed a little, and its point brought a little nearer 
to the central line of the body than that of the sound limb, for it is no longer borne off by the clavicle. The patient experiences 
difficulty in the movement of the arm, particularly in the direction upwards or forwards, his head inclines towards the affected 
side, and the clavicle no longer retains its natural position. It should be recollected that the line of that bone is not exactly 
horizontal ; its outer extremity is raised a little, so that its direction is from without inwards, downwards, and a little forwards. 
When dislocated, the slight degree of obliquity which it naturally possesses is much increased, owing to its inner extremity being 
pressed downwards and forwards upon the sternum, where it forms a prominent tumour. This dislocation is more likely to 
happen in females and in young male subjects than in adult males. It may be produced by a forcible retraction of the shoulders 
or by a fall upon the point of the shoulder. Its reduction is easily effected, by placing the knee between the scapula?, and then 
drawing the shoulders backwards, when the bone will drop into its natural position ; but it will slip out of its place again if the 
arm be not supported, and the shoulder borne off from the side by the application of a pad in the axilla supported by a proper 
bandage, the arm being at the same time kept in a sling. Boyer expresses a decided opinion, that the sternal end of the clavicle 
cannot be dislocated backwards, at least by any of the ordinary causes which produce such accidents. Sir A. Cooper says he 
has never known this dislocation to occur from violence, and that, if ever it did happen, it could only be from a blow upon the 
tore part of the bone, which would rupture the sterno-clavicular and costo-clavicular ligaments, and force the bone directly 
backwards ; but of this there is no instance on record. This displacement was, however, produced by a slow and gradual process 
in a person whose spine was distorted so much as to cause the scapula at one side to advance forwards and press the clavicle 
constantly backwards and inwards. In process of time the posterior sterno-clavicular ligament gave way, and the end of the 
bone slipped back behind the sternum, so as to produce considerable distress by its pressure on the oesophagus,— so much so that 
nothing but its removal could have saved the life of the individual. 

The external or scapular end of the clavicle may be displaced from its connexion with the acromion process by a fall on the 
point of the shoulder, which will press the scapula downwards and inwards so as to separate it from its connexion with the 
clavicle. The shoulder of the affected side is necessarily depressed and inclined a little inwards. By making pressure along the 
spine of the scapula with the fingers, it is readily ascertained that the acromion process is no longer on the same plane with the 
end of the clavicle, but is sunk somewhat beneath it. The depression of the shoulder causes the skin to be drawn tightly over 
the projecting end of the clavicle, which renders every movement of the part painful. Finally, if the shoulders be drawn 
steadily back, so that the acromion maybe carried outwards and upwards to its proper level, the displacement is at once reduced, 
but it will speedily recur if the shoulders be left without support. From this it follows, that in the management of such an 



23 

accident, adequate means should be devised to raise the scapula and bear it off from the side, the arm being at the same time 
supported so as to prevent its weight from depressing the scapula.* 

Dislocations of the Shoulder. — The head of the humerus may be displaced from the glenoid cavity of the scapula, in either 
of three directions ; it may be forced downwards into the axilla, or forwards and upwards, so as to be placed on the sternal side 
of the coracoid process , or backwards, so as to rest upon the posterior surface of the scapula :— finally, a partial displacement 
may occur, in which the head of the bone does not entirely leave the glenoid cavity, but rests partly on its inner border, and 
partly on the outer side of the coracoid process. The displacement backwards is a rare occurrence ; it often occurs in the direction 
forwards ; but by far the most frequent form of the accident is that in which the bone is pressed downwards. 

When dislocation into the axilla has occurred, the limb is necessarily lengthened, which is rendered obvious if the patient is 
viewed from behind, and the position of the elbows be compared one with the other. The arm is thrown somewhat outwards, 
so that the elbow is removed from the side, and on examining attentively the direction of the axis of the arm, it will be 
found that, instead of passing upwards from the elbow to the point of the shoulder, it inclines inwards, so as to terminate 
about two inches below that point that is a little beneath the border of the glenoid cavity. The shoulder no longer presents that 
rounded form which naturally marks it, and which depends on the support which the deltoid muscle receives from the head of 
the humerus. In the new state of parts consequent on the displacement of the bone, a depression exists instead of a fulness, 
and the want of support is readily perceived, if the fingers are pressed from point to point along the shaft of the humerus 
upwards, to where the deltoid appears sunk in. As the muscle last named is stretched, owing to its points of attachment being 
farther apart than in their natural condition, the border of the acromion process is rendered prominent, giving an appearance of 
sharpness to the shoulder. On searching for the head of the bone, it will very readily be found in the axilla, and can be distinctly 
felt, if the arm is drawn outwards a little. The power of voluntary motion is in a great degree lost ; the patient can no longer 
move his arm upwards, or raise it towards his head ; he can, however, move the limb a little forwards and backwards as it hangs 
by his side. The limb may be drawn outwards, and elevated a little, without causing much pain ; but any effort to depress it, so 
as to bring it nearer to the side, is strongly opposed by the action of the deltoid, and productive of much pain, owing to the 
pressure of the head of the bone upon the nerves ; hence it is that to relieve the pain and lessen the tension of the muscles, the 
patient instinctively inclines his head, and even his body, to the affected side, and supports and steadies the limb, by holding the 
fore-arm or elbow with the other hand. 

This displacement may be produced by a fall on the point of the shoulder, or by falling on the side with the elbow thrown 
outwards, or by falling forwards with the hands outstretched. In the two latter cases, it results partly from external violence, 
but still more from muscular action. For when the body comes to the ground with the elbow thrown out from the side, the line 
of the arm is inclined to that of the body at a considerable angle ; the lower end of the arm becomes fixed by its pressure against 
the ground, the upper end rests obliquely against the glenoid cavity of the scapula, and the muscles which form the folds of the 
arm-pit, are stretched across from the body to the humerus into which they are inserted. Under such circumstances, it represents 
a lever of the third order, the fulcrum being at the lower end, the resistance being at the upper, and the power, viz. the muscles, 
being between both; from which it follows, that if the muscles are thrown into action, they will instantly overcome the slight 
resistance given to them at the shoulder joint, and draw the bone downwards into the axilla. 

The capsular ligament is torn not only at the lower part of the glenoid cavity, but also along the whole length of its inner 
margin. The head of the bone rests on the lower border of the scapula to the inner side of the long head of the triceps 
muscle. The tendon of the subscapular muscle is also torn, the deltoid is stretched, and its fibres elongated, the supra and infra 
spinatus muscles are necessarily stretched too ; the teres major and minor muscles suffer little change ; but the coraco-brachialis, 
the biceps, and the long head of the triceps muscles are all stretched. 

If it is admitted as a general principle, that in the management of dislocations the muscles should be relaxed as much as 
possible, more particularly those which are in any way put on a stretch by the new condition into which the bones are placed, 
there can be little doubt as to the position into which the arm and fore-arm should be put in order to reduce with most ease the 
form of dislocation we are now considering. The deltoid and supra-spinatus muscles are most effectually relaxed by drawing 
the arm outwards and upwards from the side until it is brought into the horizontal position, so as to form a right angle with the 
body. Again, the biceps muscle is relaxed by bending the fore-arm upon the arm so as to form an acute angle with it. Yel 
this is not the position most commonly adopted; the dislocation is often reduced by placing the arm at full length parallel with 
the body, fixing the heel in the axilla, and pulling at the wrist, in which position every muscle which is placed in an unnatural 
degree of tension by the dislocation of the bone is rendered still more tense, and necessarily gives much more resistance than it 
would do if the limb were placed in the position above indicated. The same remark applies to the practice of reducing the 

* If care be not exercised in treating dislocation of the humeral end of the clavicle, to keep the scapula well out as directed in the text, by means of a pad 
in the axilla, the end of the clavicle will ride over the acromion, and the usefulness of the upper extremity be much impaired. A mismanaged case of this 
description, is now under my notice. The arm cannot be brought freely round upon the chest ; the clavicle no longer sewing its purpose of a nun 
with a joint at each end, the fulcrum being at the sternum; but slides over the acromion in the attempt, so as to make an unusual prominence under tin skin, and 
excite considerable pain. — J. P. 



21. 

dislocation by placing the knee in the axilla. The objection is lessened in some degree, when extension is made from the arm 
above the elbow, the fore-arm being flexed. Both modes of practice, however, succeed in recent dislocations with sufficient 
facility, but if they produce much more pain than accompanies the reduction, when care is taken to relax the muscles, then the 
motive for their continuance must be that they require little apparatus, and that success justifies their continuance.* 

The humerus may be thrown forwards and inwards off the glenoid cavity ; in which case its head will be lodged at the 
inner side of the neck of the scapula; it is also drawn upwards so as to be placed upon a level with the second rib at the inner 
side of the coracoid process, and beneath the clavicle. In this dislocation, the arm is necessarily shortened ; the elbow is thrown 
outwards from the side and also backwards. The margin of the acromion process is prominent, and the depression beneath it is 
more perceptible than in the dislocation downwards. On tracing the direction of the axis of the arm, it will be seen to drop to 
the inner side, and above the glenoid cavity ; and if the hand be placed beneath the clavicle, a tumour can be felt under the 
pectoral muscle, which will be found to move or roll if the elbow be rotated. The movements of the limb are very much 
restricted ; the arm is with difficulty drawn outwards from the side, for it is checked by the coracoid process : if it be drawn 
forwards, its head is pressed against the venter of the scapula, and the rotator muscles restrict its motion backwards. The 
diagnostic marks of this dislocation are thus briefly summed up by Sir A. Cooper : " The head of the bone is below the 
clavicle, the elbow is separated from the side, and thrown backwards ; and rotation of the arm gives motion to the head of the 
bone in its new position." 

Though the movements of the limb are thus restricted, the pain which is felt is not so great as in the other dislocation, for 
the nerves are not so much compressed. This accident commonly results from a fall when the arm is thrown out from the side, 
and a little backwards, by which means the head of the bone is forced forwards and upwards, tearing through the inner side of 
the capsular ligament. The bone in its new situation has in front of it the pectoralis minor as well as major ; its outer side is in 
immediate contact with the venter of the scapula — the subscapular muscle is partly detached from the latter surface — its inner 
surface is separated from the ribs by the fibres of the subscapular muscle, and the serratus magnus. The rotator muscles are 
stretched, as well as the posterior fibres of the deltoid muscle ; the part of the latter which arises from the clavicle is relaxe/1, so 
is the pectoralis major. This dislocation may be reduced by placing the heel in the axilla, and making extension from the arm 
immediately above the elbow, having previously placed the limb in a state of flexion, in order to relax the biceps muscle; but 
this method is not so often resorted to in the present case, as in the dislocation ddwnwards. Counter-extension is effected by 
means of a bandage or girth, so applied as to fix the scapula ; and extension is made from the arm above the elbow, the fore-arm 
being bent, so as to relax the biceps ; the limb should be drawn downwards and a little backwards, corresponding with the line 



PLATE XL 

Shows the deep-seated muscles at the side of the neck and the chest; also the subscapular muscle, to expose which all the parts in the 
axilla must be removed, and the scapula drawn backwards out of its place. 

No. 1. Part of the occipital bone. 2. The mastoid process of the temporal bone. 3. The styloid process. 4. The bodies of the cervical 
vertebrae. 5, 5. The inner and outer ends of the clavicle, the intermediate part being cut away. 6. The acromion process of the 
scapula. 7. The coracoid process. 8. The ligaments which connect it with the under surface of the clavicle. 9. The upper angle 
of the scapula. 10. The upper part of the humerus. 11. The lower border of the scapula. 12. The ligament connecting the first 
rib with the clavicle. 13. The sternum. 14. Its cartilaginous appendage. 15. The sternal or true ribs. 16. Three of the asternal 
or false ribs. 17. The line of the base of the scapula. 18. Part of the complexus muscle. 19. Part of the splenius 20 The 
elevator muscle of the angle of the scapula, (m. levator anguli scapula*; l'angulaire,) which is attached at one end by three or four 
tendinous points to the transverse processes of the upper cervical vertebra, and by the lower to that part of the base of the scapula 
which lies above its spine. 21. The posterior scalenus muscle, which is extended from the first and second ribs at their back part to 
the transverse processes of the six lower cervical vertebrae. 22. The anterior scalenus muscle, extending from the inner border and 
upper surface of the first rib upwards, to the transverse processes of the cervical vertebra, from the third to the sixth. 23. The part 
of the first rib which is included between the scaleni muscles, and over which slides the subclavian artery as it passes from the neck 
into the axilla. 24. The subscapular muscle, (m. subscapularis,) which in the natural position of the parts lies deeply in the axilla 
under cover of the scapula.-(Plate X., fig. 2, No. 17.)— It is here thrown forwards by the eversion of the shoulder, which shows its 
points of origin from the concave surface and the base of the scapula 17, and its insertion into the small tubercle of the humerus. 
25. The great serratus muscle, so called from its mode of attachment to the ribs by a series of angular processes resembling the teeth 
of a saw. The muscle is of considerable extent; it rests upon the external surface of the nine upper ribs and the intercostal spaces, 
and is inserted into the whole length of the base of the scapula, the greater number of its fibres being concentrated at the lower and 
upper angles of the bone. 26. The intercostal muscles. 

* M. Malgaigne, of Paris, has lately introduced the following method for reducing the luxation into the axilla, which, more effectually than any other, relaxes 
the two resisting muscles, the supra-spmatus and deltoides. The patient lies down imnn thp siA* ti,„ „ . j , , , i • . , • ,„, . 

.,..,,. , \ ; , . ,, <= paucm nes uuwn upon the side. l he surgeon is seated above and behind him. The scapula 

is well fixed, by placing one hand or foot upon the shoulder, or passing a jack towel over it, and fixing it to the opposite comer of the bed. The elbow is then 
to be raised up from the s.de, and drawn straight up by the head, til] the head of the bone, reaching the level of the socket, slips into its place.-!. P. 



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which its axis represents in life new position in which it is placed by the dislocation. By observing this precaution, the head of 
the bone is drawn clear of the coracoid process of the scapula, but when it is moved downwards a little, so as to approach the 
glenoid cavity, the arm should be drawn forwards at the elbow, so as to facilitate the passage of the head of the bone backwards 
into the glenoid cavity. 

The head of the humerus may be thrown backwards upon the dorsum of the scapula, where it will necessarily form a con- 
siderable tumour beneath the spine of that bone, and behind the glenoid cavity. The depression beneath the acromion in this 
case is not so great as in the dislocation downwards : the direction of the axis of the limb is forwards and inwards, the arm 
being closely applied to the side, and, as it were, inverted. When the elbow is rotated, the protuberance formed by the head of 
the bone in its new situation can be readily felt beneath the spine, and farther back than the point of the acromion process. In 
one casa cited by Sir A. Cooper, free motion was practicable backward and forward, but the limb could not be raised, or carried 
from the side without great difficulty, (on Dislocations, p. 416 :) — whilst in another, p. 404, the arm could be moved considerably 
either upwards or downwards, but the motion in the anterior, or posterior direction, was very limited. In the few cases of this 
accident which we find reported, the reduction was easily effected. The counter-extension is made in the same way as in the 
other dislocations : by a gradual extension the limb is drawn directly outwards, so as to dislodge the bone from the dorsum of 
the scapula ; if the elbow be then inclined a little backwards, the head of the bone will readily slip into its place. 

A partial dislocation of the humerus has been known to occur in a few instances. In these, the head of the bone was not 
thrown altogether off the glenoid cavity ; it rested partly upon its inner margin, and partly upon the contiguous portion of the 
coracoid process. The position of the bone thus placed, distinguishes the accident from the complete dislocation ; for in the latter 



PLATE XII. 

Fig. 1. Shows the fascia of the arm, and of the palm of the hand. No. 1. The inner end of the clavicle, the bone being fore-shortened in 
an extreme degree. 2. The coracoid process. 3. The subscapular muscle, its fibres being partly concealed by a thin membrane or 
fascia. 4. The anterior part of the deltoid muscle. 5. The tendon of the latissimus dorsi. 6. Part of the pectoralis major muscle: 
between the two last are seen, 7. The coraco-brachialis, and 8. The short head of the biceps muscle, passing down from their attach- 
ment to the coracoid process. 9. The fascia rendered prominent by the projection of the belly of the biceps muscle. 10. Indicates 
the place of the triceps. 11. Lies over the point into which the coraco-brachialis is inserted. 12. The position of the inner condyle. 
13. Fibres given off from the tendon of the biceps muscle, which strengthen the fascia. 14, 15,16, 17. Indicate the points at which the 
fascia is stretched over the supinator longus, flexor carpi ulnaris, palmaris longus, and flexor carpi radialis. 18. The palmar fascia: 
farther on it widens and presents distinct points of attachment to the extremities of the metacarpal bones. External to it are seen the 
muscles of the thumb. Those of the little finger lie to its inner border. 
Fig. 2. Shows the fascia on the posterior and external part of the arm and fore-arm. 

No. 1. The acromion process. 2. The spine of the scapula. 3. The thin part of the fascia covering the deltoid muscle. 3. bis. The 
dense fascia covering the infra-spinatus muscle. 4. The fascia, where it covers the biceps muscle. 5. The place of the triceps. 
G. The place of attachment of the fascia to the external condyle: — 7. To the external ridge of the humerus. 8, 9, 10. The fascia 
strained over the supinator, the common extensor, and the ulnar extensor. 11. The posterior annular ligament of the wrist. 12. The 
fascia covering the back of the hand, which is so thin as to allow the tendons of the extensor muscles to be seen through it. 

Fig. 3. Shows the posterior annular ligament of the wrist, and the sheaths which it forms for the transmission of the tendons of the 
extensor muscles. The wrist joint has been cut across, and the radius and ulna sawed through immediately above it. 

No. 1. The articulating surface of the radius. 2. The triangular ligament, which connects its inner border with the styloid process of the 
ulna. 3. The posterior annular ligament of the carpus. 4. The canal for the extensors of the metacarpal bone and first phalanx of 
the thumb. 5. One which is common to the tendons of the extensor carpi radialis, longior and brevior. 6. The canal for the trans- 
mission of the extensor of the second phalanx of the thumb. 7. One for the common extensor, and the indicator muscle. 8. That 
for the extensor of the little finger. 9. The sheath, or rather canal, which transmits the tendon of the flexor carpi ulnaris muscle. 

Fie. 4. Shows the anterior annular ligament of the wrist, as it is stretched across from its inner to its outer border, forming with the carpal 
bones a ring or canal, for the transmission of the flexor tendons. 

No. 1. The anterior annular ligament of the wrist. 2. The pisiform bone. 3. The trapezium. 4. The cuneiform bone. 5. The semi- 
lunar. G. The scaphoid bone. 7. The ring which transmits the flexor tendons, near which is the small ring for the tendon of the 
flexor carpi radialis. 

Fig. 5. Gives a side view of one of the fingers, in order to show the fibrous band or sheath which binds down the tendons of the flexor 
muscles; and the manner in which the interosseus and lumbricales muscles become fixed into the expanded tendon of the extensor 
muscle. 

No. 1. A metacarpal bone. 2. The fleshy fibres of an interosseus muscle. 3. A lumbricalis muscle arising from 4, one of the tendons of 
the deep flexor muscle. 5. The extensor tendon running along the dorsal surface of the bone, and prolonged upon the phalanges of 
the finger. G, 7. The insertion of the interosseous and lumbricalis into the border of the extensor tendon. 8. The tendon of the 
superficial flexor entering the sheath. 9. The fibrous sheath, which binds down the flexor tendons as they run along the palmar 
aspect of the finger. 

Fie. G. The same ringer placed in the bent position, in order to show how the sheath binds down the flexor tendons, and increases their 
power; also how the lumbricales and intcrossei may become flexors of the first joints of the fingers. 
Muscles. — 4 



26 

it lies at the sternal side of the coracoid process, and in the former at the scapular side. It may be produced by a fall on the 
shoulder ; after which, the shoulder no longer retains its usual roundness : a depression exists over the hack part of the shoulder 
joint, so that the posterior half of the glenoid cavity can be perceived to be unoccupied by the head of the bone. When the 
upper extremity of the hone is thus thrown forwards and inwards, its axis will necessarily incline from above downwards, and a 
little backwards and outwards : the limb cannot be raised directly from the side, for by that movement the head of the bone is 
made to strike against the coracoid process, but if the elbow be drawn a little forwards, it may then be carried upwards. This 
form of dislocation is easily reduced ; but it has a tendency to slip forwards again. The extension and counter-extension are made 
in this case in the same manner as in the dislocation forwards; but it is " necessary to draw the shoulders backwards, in order 
to bring the head of the bone to the glenoid cavity : immediately when the reduction is completed, the shoulders should be bound 
back by a clavicle bandage, else the bone will immediately slip forwards against the coracoid process." (Sir A. Cooper on Dis- 
locations, p. 410.) If the clavicle bandage cannot conveniently be procured, a moderately sized pad may be placed in the axilla, 
and the elbow drawn forwards and inwards to the side of the chest, and retained in that position by a circular bandage, carried 
round the body. When the arm is thus placed, it must be obvious that the head of the bone is directed backwards and outwards, 
and thereby kept in apposition with the glenoid cavity of the scapula.* 



PLATE XII. 

Tins plate gives back and front views of the thin firm membrane which invests the muscles of the arm and fore-arm- it 
binds down the muscles like a band or sheath, from which circumstance it is called fascia; it is placed immediately beneath the 
skin, with which it is connected by cellular tissue, by small blood vessels and filaments of nerves, which must pierce this mem- 
brane before they can reach the tegument. The fascia resembles a web composed of white shining fibres, which run in various 
directions, some transversely, and others longitudinally, so as to form a layer of membrane ; the outline of the muscles can be 
distinctly traced, even while they are covered by the fascia, for the membrane is closely adherent to them, and also gives ofTfrom 
its inner surface thin plates, which project into the interstices between several of the muscles, like so many partitions. The 
membrane is not of uniform thickness throughout its entire extent; it is thicker and firmer on the back part and outer side of the 
limb, than on the inner and fore part. At the bend of the elbow, the fascia is intimately connected with the condyles of the 
humerus, and also with the two ridges which extend upwards along the bone from these prominent processes; the latter con- 
nexion is effected by means of two firm plates of membrane, similar in structure to the fascia, which pass from its inner surface. 
to the bone, so as to form partitions between the extensor and flexor muscles; from which circumstance they are termed inter- 
muscular ligaments. They serve, however, another purpose ; they give an increased surface of attachment to the muscles, for 
several of the fibres of these arise from them. The inter-muscular septum at the outside of the arm, reaches from the external 
condyle to the insertion of the deltoid ; that at the inner side, from the corresponding condyle upwards to where the coraco- 
brachialis muscle is inserted. 

At the outer side of the arm, the fascia is intimately connected with the insertion of the deltoid muscle, at which point it is 
strong and firm ; but when traced upwards over the muscle, it becomes thin, so as to resemble a slight layer of condensed cellular 
tissue, rather than an investing membrane. In this altered form, it reaches as far as the spine of the scapula, and the outer part 
of the clavicle ; behind the border of the deltoid it becomes blended with a very dense and firm membrane, which covers the 
infra-spiuatus muscle. At the inner side of the limb it gradually becomes weak as it approaches the axilla ; but it can be traced 
upon the pectoral muscle, and the latissimus dorsi, where they form the folds of the axillary space, for it is stretched across from 
the one to the other : from this point it gradually degenerates into mere cellular tissue, as it reaches the side and fore part of the 
thorax. 

The fascia of the fore-arm is very dense and firm, particularly at the back part, and along the ulnar border ; at the wrist, it 
is inserted into the annular ligaments. Its outer surface is separated from the tegument by the superficial veins, nerves, and 
lymphat.es; its inner surface is intimately connected with the fibres of the muscles which arise from the condyles and moreover 
gives off thin layers, which lie between them like so many septa, at the same time that they increase their points of attachment, 
for several of the muscular fibres arise from them. 

The anterior annular ligament of the wrist is a strong firm band of white shining fibres, stretched across from one bordei 

* Young children are particularly liable to this form of subluxation of the humerus, a fact which I believe has not been noted. Four cases of the kind have 
come under my not.ee in the last three years, resulting from falls upon the shoulder. Slight efforts sufficed to replace the bone in each case, and the recovery of 
the perfect use of the hmb was so speedy as to make it probable that in these instances the capsular ligament had been stretched but not torn in the displacement 
of the head of the bone. In one case the diagnosis was at first rendered obscure by a slight crepitation, resulting from an inflammatory thickening of the tissues 
about the joint. — J. P. ° J ° 



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of the carpal bones to the other, so as to convert the groove which these bones form into a canal. (Plate XII. fig. 4.) Its outer 
end is attached to the fore part of the trapezium and scaphoid bones, the inner to the pisiform bone, and the unciform. The 
fascia of the arm is attached to its upper edge, and to the lower is fixed the palmar fascia : its anterior or superficial surface gives 
attachment to some of the muscles of the thumb, and of the little finger ; the posterior is in apposition with the tendons of the 
flexor muscles which slide beneath it. This surface is lined by a synovial membrane, which is prolonged upwards and down- 
wards upon the flexor tendons, and dips in between them so as to facilitate their various movements ; the tendon of the long 
flexor of the thumb has a distinct synovial sheath. 

The posterior annular ligament of the wrist is stretched obliquely across the extensor tendons, and retains them in their 
situation. It is not by any means as strong or firm as the anterior ligament ; its external extremity is attached to the outer part 
of the radius, from whence it is stretched inwards, and turning round the inner border of the wrist becomes attached to the pisi- 
form bone, and the anterior annular ligament. Its upper border gives attachment to the fascia of the arm, (Plate XII. fig. 2, No. 
11 ;) from the lower extends a thin fascia which covers the back of the hand, No. 12. Its posterior surface is subjacent to the 
skin ; and from the anterior, bands are given off which are interposed between the tendons of the muscles, and by becoming 
fixed to the different prominent points upon the surface of the bones, convert into canals the shallow grooves which are marked 
upon the lower ends of the radius and ulna. (Plate XII. fig. 3.) These canals are lined by synovial membranes, which are 
reflected upon the tendons for some way both upwards and downwards. 

The palmar fascia, (Plate XII. fig. 1, No. 18,) is a dense firm layer of fibrous structure, and of a triangular form, which 
extends from the anterior annular ligament of the wrist to the extremities of the four metacarpal bones, which support the fingers. 
Its narrow part or commencement is attached to the anterior annular ligament of the wrist, and to the tendon of the palmaris 
longus muscle. When traced forwards over the metacarpal bones, its fibres divide into four separate bundles, which are directed 
towards the extremities of the metacarpal bones : there each divides into two slips which diverge so as to leave a free passage 
for the transmission of the flexor tendons, and of the nerves and vessels. The slips or processes here alluded to, as they turn 
backwards, become fixed to the transverse and anterior metacarpal ligaments. The fibres, which in this arrangement run forward 
from the anterior ligament to the metacarpal bones, are interwoven with others which run in a transverse direction, so as to pre- 
vent their being separated or torn. From the edges of the palmar fascia thus disposed, a thin lamella projects inwards over the 
muscles of the little finger, and outwards over those of the thumb. The superficial surface of the fascia is subjacent to the skin ; 
the deep one rests upon the flexor tendons and the palmar nerves and vessels, which it binds down and conceals. 

PLATE XIII. 

These two drawings show the muscles which are in intimate relation with the shoulder joint. 

Fig. 1. No. 1. The clavicle. 2. Its outer end. 3. The acromion process of the scapula. 4. The ligament which connects these two 
bones. 5. The spine of the scapula, which is here greatly fore-shortened as the parts are viewed laterally: part of the supra-spinatus 
muscle is seen above it. 6. The deltoid muscle. 7. Its insertion into the humerus. 8. Part of the infra-spinatus muscle. 9. Part 
of the teres minor muscle. 10. The origin of the teres major muscle. 11. Part of the biceps muscle. 12. The origin of the brachialis 
anticus muscle, immediately below the insertion of the deltoid. 13. The long head of the triceps muscle. 14. The second or external 
head of the same muscle. 

Fig. 2. Shows the external rotator muscles as they are seen from behind ; the deltoid is removed in order to expose their insertions, as well 
as the points of attachment of the teres major muscle, and the origin of the two heads of the triceps. 

No. 1. The acromion process. 2. The spine of the scapula. 3. The base of the scapula. 4. Its inferior angle. 5. The great tuberosity 
of the humerus. 6. The shaft of the bone drawn obliquely outwards and forwards. 7. The supra-spinatus muscle. 8. Its tendinous 
insertion into the upper part of the great tuberosity of the humerus. 9. The infra-spinatus muscle. 10. The teres minor muscle. 
11. Its insertion into the lower part of the great tuberosity of the humerus. 12. The teres major muscle. 13. Its insertion into the 
posterior border of the bicipital groove of the humerus. 14. The long head of the triceps muscle; its fibres coming downwards from 
the lower border of the scapula; its origin, however, is here concealed by the teres minor. 15. The second or middle head of the 
triceps muscle, arising from the shaft of the os humeri; its upper fibres form a pointed process, which reaches nearly as far as the 
insertion of the teres minor into the great tuberosity of the humerus. 16. Part of the deltoid remaining at its insertion, the rest 
being cut away. 



28 



PLATE XIV. 

The drawings in this fasciculus are intended to show the muscles which act upon the fore-arm, and bring it forwards, so as 
to form an angle with the upper arm, and those which carry it back again, so as to bring the whole limb into a straight position. 
These movements are termed flexion and extension. The elbow-joint is constructed on the principle of a hinge, the movements 
of the fore-arm upon the arm being limited to those here stated. The two muscles which bend the fore-arm upon the arm, are 
shown in Plate XIV. fig. 1. They are placed upon the fore part of the shaft of the bone. The first of these is placed in the 
greater part of its extent immediately beneath the skin and the fascia of the arm as is seen delineated in Plate XII. fig. 1, No. 9. 
It extends from the scapula down to the radius or outer bone of the fore-arm, and is named the two-headed flexor of the fore- 
arm, (biceps flexor cubiti.) This term expresses the fact, that it flexes the fore-arm, and that at its upper extremity it presents 
two heads or distinct points of attachment: one of these is observed to be fixed to the coracoid process of the scapula conjointly 
with another muscle which lies along its inner border, and which, from being attached by one end to the process just named, and by 
the other to the arm-bone about its middle, is named coraco-brachialis ; the other head of the biceps runs over the upper extremity 
of the humerus in a groove which lodges it, and through the capsular ligament of the shoulder-joint, as may be seen in fig. 2, 
No. 7, its extremity being fixed to the upper border of that shallow pit in the scapula with which the head of the humerus 
articulates. These parts of the muscle are compressed and narrow ; they are here shown of a white colour, for they consist of 
tendinous fibres. They gradually approach as they descend, forming a very acute angle, and widen somewhat as they become 
continuous with the fleshy part or body of the muscle, which will be observed to enlarge and swell out, becoming convex and 
prominent at its middle ; but towards the lower part it again narrows, and its fibres run into a tendon which slides over the 
elbow -joint, and is fixed to a prominent nodule of bone which projects from the inner side of the radius. When the fleshy fibres 
of the biceps muscle are brought into action, they contract and shorten, by which means its ends are necessarily brought nearer 
to one another. But, as the upper end is for the most part fixed, the power of the muscle is concentrated upon the lower one, by 
which means the radius is drawn forward, so as to form an angle with the humerus. The action of the muscle, however, is not 
confined to one of the bones of the fore-arm ; by a simple piece of mechanism, it is made to extend in effect to the other also ; 
for from the inner border of its tendon a fibrous band is stretched obliquely inwards, and becomes fixed upon the surface of the 
muscles of the fore-arm. This fact is expressed in Plate XII. fig. 1, No. 13. By means of this process, and of the connexion 
which it establishes, whenever the muscle contracts, so as to pull upon the radius, part of its effort is directed at the same time 

PLATE XIV. 

Fig. 1. Shows the two flexor muscles of the fore-arm, and the extensor as seen from the inner side of the limb. The subscapular muscle 
is also brought into view ; to effect which the scapula and arm are detached from their connexions with the body. 

No. 1. The acromion process of the scapula. 2. The coracoid process. 3. The upper border of the scapula. 4. Its upper angle. 5. The 
base. 6. The lower angle. 7. The small tubercle of the humerus. 8. The inner condyle. 9. The outer condyle. 10. The 
tubercle of the radius. 11. Part of the shaft of the radius. 12. Part of the ulna. 13. Part of the supra-spinatus muscle. 14. The 
subscapular muscle. 15. Part of the teres minor muscle, deeply shaded where it crosses behind the long head of the triceps muscle. 
16. The teres major muscle. 17. Part of the latissimus dorsi muscle. 18. Part of the pectoralis major drawn forwards out of its 
place. 19. The external or long head of the biceps muscle. 20. The inner or short head arising from the coracoid process, together 
with the coraco-brachialis muscle, which lies along its inner border. 21. The rounded tapering body of the biceps muscle. 22. Its 
tendon of insertion into the tubercle of the radius. 23. The posterior or long head of the triceps muscle. 21 . Its inner or short head : 
between the latter and the biceps appears the brachialis anticus muscle, marked 23, but which ought to be 25 ; its insertion into the 
coronoid process of the ulna is seen further down. 

Fig. 2. Shows the capsular ligament of the shoulder-joint laid open, in order to bring into view the tendon of the biceps muscle— its relation 
to the head of the bone, and its origin, form the upper border of the denoid fossa. 

No. 1. The hollowed or under surface of the scapula. 2. The coracoid process. 3. The acromion. 4, 5. The globular head of the 
humerus. C. The glenoid ligament surrounding the margin of the articular cavity of the scapula, and connected with 7, the tendon of 
the biceps muscle. 6. Is the shaft of the humerus. 8. The capsular ligament of the joint laid open. 9. The tendon of the biceps 
after having passed beneath the border of the capsular ligament. 

Fig. :». Exhibits in its entire length the supra-spinatus muscle ; the scapula and shoulder joint being viewed from behind. 

Mo. 1. The posterior surface of the scapula. 2. The spine; the acromion is removed where it overlaps the supra-spinatus muscle. 
3. The upper part of the base of the scapula. 4. The neck of the bone. 5. The capsular ligament where it covers the head of the 
humerus. 6. Part of the shaft of the humerus. 7. The supra-spinatus muscle. 8. The insertion of the infra-spinatus muscle into 
the "rent tubercle of the humerus. 



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29 

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upon the inner side of the fore-arm. Another simple contrivance gives to this muscle an additional power over the radius besides 
that of flexion. If it were intended to give it the latter power alone, its tendon would have been fixed into the anterior surface 
of the bone : its fibres, however, are prolonged backwards, and fixed towards the posterior aspect of a nodule of bone called its 
tubercle which projects from the side of the radius, so that it is thrown inwards from the axis or shaft of the bone. Now, if the 
radius is rotated inwards, as when we turn the hand and fore-arm prone, the biceps muscle is enabled to rotate it upon its axis, 
and turn the arm and hand outwards, bringing thereby the palm of the hand from the prone into the supine position. 

When we consider the changes which occur in this muscle during its actions, it is obvious that a loss of power results, not 
only from the mechanical contrivance employed, but also from the circumstance, that part of its force is expended upon the 
scapula ; for when the fleshy fibres contract, they ripple and concentrate themselves towards the middle of the muscle, thereby 
pulling upon both ends — the upper as well as the lower. But though some force is thus directed away from the fore-arm, it cannot 
be considered as either lost or misplaced, when we take into account the influence which it exerts upon the state of the limb 
generally. The power applied in this direction, has the effect of drawing the articulating cavity of the scapula into closer 
apposition with the humerus, and the latter bone is at the same time prevented from sliding upwards, during the action of the 
muscle, by which adjustment the humerus is made to constitute a sufficiently steady point of support for the arm-bones. The 
mechanism by which this is effected will readily be perceived, by looking at fig. 1, in the plate; it shows how an associated 
movement is established between the three bones — the radius, the humerus and the scapula. Other muscles, as well as the 
biceps, are concerned in these movements, and are made to perform, either together or separately, various parts in the changes 
which take place, and in the efforts which are made ; it too fulfils its own purposes in the ways here pointed out. 

As to the other mode in which power is lost, for it, also, ample compensation is afforded. In the movements of the arm, the 
radius is made to serve as a lever, the muscles being the moving power by which it is acted on. The fulcrum or point upon 
which it rests or moves is in the elbow-joint, where the head of the bone rests against the humerus ; the resistance is at the 
opposite end, viz. at the hand, the power being between both, so that it represents a lever of the third order : moreover, in 
originating the motion, the muscle acts in a direction nearly parallel with the axis of the radius. A loss of power obviously 
results from this contrivance ; but a considerable degree of velocity is acquired in the movements of the limb, which is a sufficient 
equivalent for the loss. 

The biceps muscle has a powerful assistant in the muscle (brachialis anticus,) which is placed immediately under it, and part 
of which is in this plate seen, fig. 1, No. 23, projecting from under its inner border, and extending downwards, to be fixed 
into the fore part of the ulna at its coronoid process. The muscle extends from the middle of the humerus to the point just 
named; it commences (see Plate XV. fig. 1, No. 13, where it is shown in its entire length, the biceps being removed,) just below 
the insertion of the deltoid muscle, which it in a manner embraces by its bifid extremity, and its fibres take their points of attach- 
ment from thence downwards along the surface of the humerus ; its insertion is into the fore part of the coronoid process of the 
ulna. The direct action of the muscle is to draw the ulna forwards on the humerus, thereby conspiring with the biceps muscle 
in flexing the fore-arm. 

The antagonist of the flexor muscles is in part seen in this drawing; it is called the three-headed extensor muscle, (triceps 
extensor cubiti.) The parts which it here presents, are indicated by the figures, 23, 24. It is fully shown in Plate XV. fig. 2. 
Its points of attachment and action shall be given in our comments upon the latter. 

Two muscles are here shown, which exert considerable influence on the movements of the arm; one of these is seen in fig. 
1, No. 14, another, No. 16 ; the former is triangular in its figure, taking the form of the scapula, and under cover of which it is 
placed, from which circumstance it is called the subscapular muscle. Its fibres are attached by one extremity to that surface of 
the bone just named where it overlays the ribs, by the other they are fixed to the humerus through the medium of a tendon, 
towards which they are seen to converge : — the tendon, previously to its insertion into a nodule upon the bone, called its small 
tuberosity, is intimately connected with the fibrous capsule of the shoulder-joint. This muscle when brought into action will, in 
the first instance, press the head of the humerus closely to the articular cavity of the scapula, and continuing its action it rotates 
the bone inwards making it to turn upon»its axis. The subscapular muscle and the three others which extend to the humerus 
from the posterior surface of the scapula, and which are seen in Plate XIV. fig. 2, No. 7. 9. 10, are the principal agents in 
keeping the head of the humerus in its place, as well as in rotating it. The weight of the limb tends constantly to draw it 
downwards, and the capsular ligament which connects it with the scapula, would be altogether insufficient to sustain it, but for 
the contractile force and power of these muscles. This is proved by the facility with which dislocations are known to occur, in 
cases in which paralysis has weakened or destroyed the power of the muscular fibres, and by the readiness with which displace- 
ment is known to recur in certain individuals, owing to a state of atony induced by previous dislocation. 

Below the subscapular muscle is seen another called the teres major, No. 16, a name which is obviously ill-chosen, for it 
does not correctly express what its form is ; and resting upon it is seen part of the broad muscle of the back, (latissimus <1 
No. 17.) These muscles when put in action can draw the shaft of the humerus inwards to the side, and, if the arm has been 
previously rotated outwards, their mode of attachment to the humerus is such as to enable them to turn it upon its axis, and rotate 
it inwards. 



30 

Fig. 3, shows the supra-spinatus muscle in its entire extent; the acromion process of the scapula heing cut away in order to 
bring its insertion into view. It extends outwards from the scapula to the large tubercle of the humerus, into which it is fixed 
by a tendinous insertion. When this muscle is coming into action, it will press the upper extremity of the humerus against the 
glenoid cavity of the scapula ; continuing its effort, it will make the rounded head of the bone slide downwards, and at the same 
time project its axis outwards from the side, making the bone to pass from the position in which it is seen in fig. 3, to that in 
which it is placed in fig. 2. Thus when we desire to move the arm from the side and carry it upwards into the horizontal posi- 
tion, this muscle commences the effort andean effect it to a certain extent; but the deltoid is called into action, takes up the 
movement at a particular point, and continues it until completed. 



PLATE XV. 

The co raco -brachial muscle is here shown in its entire length, fig. 1, No. 17, also the anterior brachial muscle, fig. 1, No. 13. 
In order to expose both of these fully, the biceps muscle has been removed; but the principal object of both figures is to show 
the extensor muscle, which is placed at the back part of the humerus, for it is opposed in situation, as it is the antagonist in action, 
to the biceps and anterior brachial muscle. It is called the three-headed extensor muscle, (triceps extensor cubiti,) the name being 
intended to express its action upon the fore-arm, and also because at its upper extremity it has three points, or heads. One of 
these heads is fixed to the lower border of the scapula, immediately behind its articulating cavity. (Fig. 1, No. 15 ; also fig. 2, 
No. 15.) At first it is flat and tendinous, but lower down it enlarges and becomes fleshy. The second head lies along the outer 
border of the bone just noticed ; it commences by a pointed tendinous process immediately below the great tubercle of the 
humerus ; the muscular fibres which are placed lower down, commence from the surface of the humerus, to which they are fixed 
from point to point, even to its lower extremity. The short head lies along the inner side of the first, as may be seen in fig. 1, 
No. 14. Its fleshy fibres, too, take points of attachment along the surface of the humerus. It would be more correct to say, 
that in this case as well as in others, the muscular fibres are attached to the periosteum or fibrous investment of the bone, rather 
than to the osseous texture itself. The muscular fibres here noticed, extend, some directly downwards, others downwards and 
backwards, and become continuous with the fibres of a broad aponeurosis seen at fig. 2, No. 11, which narrows at its lower part, 
and is fixed to the posterior surface of the olecranon process of the ulna. 

When the fore-arm is brought into a state of flexion by the action of the biceps and anterior brachial muscle, the triceps can 
readily draw it backwards, so as to bring it again into a right line with the humerus, or, in other words, extend it. If the fore- 
arm and arm be fixed, the long head of this muscle can move the scapula upon the humerus, and in the extended stale of the 
limb it may assist in drawing the arm backwards. 

Dislocations of the elbow-joint. — The bones which form the elbow-joint may be displaced from one another in different 
directions. The radius and ulna may be thrown backwards behind the humerus, or they may be forced inwards or outwards; 
but the luxation backwards is the most ordinary occurrence, owing to the manner in which the force is applied. The accident 
most commonly occurs when a person, in falling forwards, puts out his hands to protect his body. In such circumstances, the 
palm of the hand comes first to the ground, so that the force of the fall is transmitted to the fore-arm, tending to press the upper 
ends of the radius and ulna backwards behind the humerus, whilst at the same time the weight of the body presses the lower 
extremity of the humerus obliquely downwards and forwards. In this way the bones are made to ride one upon the other, their 
ends being driven by opposing forces in the directions just indicated. There is also something in the structure of the joint which 
lenders this dislocation more frequent than the others ; for the coronoid process of the ulna projects but little forwards, and opposes 
only a slight resistance to the humerus when it is pushed downwards and forwards by the fall. Another form of dislocation 
occurs, in which the ulna alone is displaced from its connexion with the pulley-like surface of the humerus, and thrown behind 
it. the radius remaining in its usual position. And lastly, the radius by itself may be forced either forwards or backwards, the 
ulna remaining in its place. These are the simple dislocations (as distinguished from those that are compound or complicated) 
winch may take place at the elbow-joint ; one, however, occasionally occurs which is not included in this list :— it is that form of 
accident in which the radius and ulna are both dislocated forwards, which is necessarily complicated with fracture of the olecranon 
process. 

When both bones arc thrown backwards, the coronoid process of the ulna is lodged in the pit at the lower part of the hume- 
rus, so that the olecranon projects backwards, and also much above its usual position. In the natural state of the parts, this 
process of the ulna is on a level with the external condyle of the humerus ; but in its new position, it projects nearly an inch and 
a halt above it. As to the radius, its position is at the back part of the external condyle of the humerus ; whilst the last-named 
bone necessarily forms a considerable prominence at the fore part of the arm. Owing to this change in the relative position of 
the bones, the shape of the limb at the elbow-joint is greatly altered. There is a considerable projection at the back part, con- 



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31 

sisting of the olecranon process and the head of the radius ; the articular surface of the humerus forms a prominence at the front, 
hut, laterally, there is a depression at each side, corresponding with the borders of the olecranon. Motion is nearly lost ; the limb 
is a little flexed, the fore-arm inclining to the supine position. The anterior ligament of the joint is necessarily torn through ; the 
biceps muscle is somewhat stretched ; and the brachialis anticus is considerably so, for it is made to run over the articular surface 
of the humerus, and then curves backwards to the coronoid process. The triceps muscle, on the contrary, is relaxed, inasmuch 
as the olecranon process, into which it is inserted, is situated higher up than in its natural condition. When the state of the two 
flexor muscles is considered, particularly that of the brachialis anticus, it will be obvious that they will begin to assist in drawing 
the bones forward, as soon as the coronoid process is dislodged from its position in the supra trochlear fossa ; to effect this primary 
object, a simple expedient will suffice. The patient sits on a chair, and the surgeon placing his foot upon it also, rests his knee 
against the inner side of the elbow-joint in which the dislocation has occurred. He then takes hold of the wrist, and draws the 
fore-arm forcibly forwards. At the moment of doing this, the pressure of the knee is directed against the radius and ulna, with 
a view to force them backwards from the humerus ; and when this is once effected, the action of the flexor muscles will draw 
the bones forwards into their natural position. Sir Astley Cooper once reduced a dislocation by the aid of the muscles alone, in 
the case of a person who had the elbow dislocated backwards, and also laterally inwards : " Finding (to use his own words) that 
the tendon of the biceps and the brachialis anticus were put upon the stretch, I thought I might make use of them to draw the os 
humeri backwards, as by the string of a pulley ; so I forcibly extended the arm, and the dislocation was immediately reduced." 
— (On Dislocations, p. 437.) The muscles, under such circumstances, doubtless exercise some influence in pressing the humerus 
backwards, but their principal force will be made to act in drawing the ulna and radius forwards. When the reduction is effected, 
the fore-arm should be bent, so as to form an angle somewhat less than a right angle with the upper arm, and should be retained 
in that position, and supported in a sling. There are various modes of effecting the reduction of this dislocation. It is a common 
practice to place the patient beside a bed-post, round which he places his arm ; the fore-arm is then drawn steadily forwards, and 
at the same time bent, but the upper-arm must necessarily be fixed, else the counter-extension will not be adequately maintained : 
again, the counter-extension may be made by an assistant, who takes hold of the middle of the arm, whilst another assistant 
makes extension from the wrist. In the dislocation backwards, it sometimes happens that the annular ligament, which retains 
the head of the radius in apposition with the side of the ulna, is torn, so that when the chief dislocation is reduced, the radius 
has a tendency to slip out of its place, and pass before the ulna. If such an accident should take place, it must be dealt with as 
if it were a primary dislocation of the radius forwards, which we shall notice in the sequel. 

The bones of the fore-arm may be thrown inwards or outwards, constituting the lateral dislocations ; these are commonly 
the consequence of considerable force or violence, for none of the ordinary movements of the arm tend to favour their produc- 
tion, and their occurrence is opposed by the mode of adaptation which exists between the articulating surfaces of the bones. It 
should also be observed, that these dislocations are seldom complete, which is owing, no doubt, to the great extent of the articu- 
lating surfaces in the transverse direction. The accident has been produced by the arm being accidentally caught between the 
spokes of the wheel of a carriage as it rolled along, by which means the fore-arm was drawn outwards, and the upper-arm 
inwards; it has been produced also by the passage of a wheel over the arm of an individual who had fallen with the limb out- 
stretched. In either case, the lateral ligaments of the joint are torn, and those upon the front and back part are partially, if not 
entirely so. The fibres of the muscles, too, suffer more or less injury ; hence it is that the limb seldom presents that fixity which 
exists in the posterior dislocation. When the bones of the fore-arm are thrown outwards, the coronoid process will rest against 
the back part of the external condyle of the humerus, so that the olecranon forms a greater projection than it does in the disloca- 
tion backwards. The head of the radius necessarily lies behind, and to the outer side of the humerus, where it can be readily 

PLATE XV. 

Fig. I. Shows the brachialis anticus muscle in its entire extent ; and two portions of the triceps are seen from the inner side of the limb. 

No. 1. The scapula — its hollowed or under surface. 2. The coraco-acromial ligament inserted into the acromion process. 3. The coracoid 
process. 4. The lower border of the scapula. 5. The great tubercle of the humerus. 6. The shaft of the bone. 7. The external 
condyle of the humerus. 8. The head of the radius. 9. Part of the shaft of the radius. 10. The coronoid process of the ulna. 1 1. 
The inner condyle of the humerus. 12. Part of the shaft of the ulna. 13. The brachialis anticus muscle. 11. The inner or short 
head of the triceps muscle. 15. Its long head. 16. A small part of the external head of the triceps, seen in the interstice between 
the long head and the humerus. 17. The coraco-brachialis muscle. 

Fig. 2. Exhibits the triceps muscle in its entire extent, as seen from the back of the limb. The scapula is drawn up in order to put the 
long head of the muscle on the stretch. 

No. 1. The dorsal surface of the scapula. 2. Its lower border. 3. The coracoid process. 4. The large tubercle of the humerus. 5. 
The small tubercle. 6. The inner condyle. 7. The border of the sigmoid cavity of the ulna. 8. The external condyle. 0. The 
head of the radius. 10. Part of the ulna. 11. The lower or tendinous part of the triceps muscle. 12. The fleshy body of the 
muscle. 13, 14. The inner or short head of the triceps. 15. The long head of the triceps muscle. 10. The extern' head of the 
muscle. 



32 

felt by rotating the hand. At the inside of the articulation the condyle of the humerus forms a projection, and there will neces- 
sarily be a depression above the one and beneath the other of these prominent points. When the bones are thrown inwards, 
the olecranon process will rest against the back part of the inner condyle of the humerus, where it forms a considerable projec- 
tion. The head of the radius corresponds with the posterior fossa of the humerus, which ordinarily receives the olecranon. In 
such circumstances, the external condyle of the humerus is rendered very prominent at the outer side of the joint, and beneath 
it there is a depression, owing to the retrocession of the head of the radius; at the inner side of the limb there is a depression 
also, but it is above the end of the olecranon. These circumstances, together with the inclination of the hand and arm outwards, 
coupled with the want of power and of motion in the limb, constitute the distinguishing characters of the accident. In whatever 
direction the dislocation has occurred, the reduction is easily effected by making counter-extension from the arm and extension 
from the wrist ; there being little resistance to overcome, save what is offered by the friction of the projecting ends of the bones 
against one another. Or the expedient above indicated, in the case of the dislocation backwards, may be resorted to, viz. that of 
" bending the arm over the knee, even without particularly paying attention to the direction of it, inwards or outwards ; for as 
soon as the radius and ulna are separated from the os humeri, by the pressure of the knee, the muscles will give them the proper 
direction for reduction." — (Op. cit. p. 436.) 



PLATE XVI. 

Some of the muscles of the fore-arm are brought distinctly into view as soon as the skin and fascia are removed, others are 
placed more deeply ; the two figures in this plate indicate the fact. Several of the muscles are attached to the prominent points 
of the humerus, so that one group will be observed to arise from the inner condyle of that bone, and another from the outer 
condyle. In the interval between these the biceps and brachialis anticus muscles are seen to dip down in order to reach their 
points of attachment to the radius and ulna. Into this interval also the brachial vessels descend as they are passing from the arm 
into the fore-arm. The names of the muscles express their ordinary actions and uses ; one is observed to stretch obliquely from 
the inner condyle, downwards and outwards, to the middle of the radius, fig. 1 — 7, 8. It is called the pronator of the radius, 
(pronator radii teres,) for it can turn the radius upon its axis, so as to place the fore-arm and hand in the prone position, if it has 
been previously in the opposite state. If, after having effected so much by its contraction, it be made to continue its efforts, it 



PLATE XVI. 

The muscles at the front of the fore-arm are exhibited iri these drawings; the superficial set, those which lie immediately under the skin 
and fascia, are represented in Fig. 1 . In Fig. 2, some of these are removed in order to bring others into view, which they in part conceal. 

Fig. 1, No. 1. The lower part of the biceps muscle. 2. Its tendon; at its inner edge is seen part of the aponeurosis given off from the 
tendon, and which, when prolonged inwards, covers the brachial artery and median nerve. 3. Its insertion into the tubercle of th& 
radius. 4. The lower part of the brachialis internus muscle projecting at each side of the tendon of the biceps. 5. Part of the triceps 
muscle. 6. The fleshy fibres of the brachialis anticus muscle. 7. The pronator radii teres muscle. 8. Its lower part becoming ten- 
dinous as it approaches the radius. 9. The flexor carpi radialis muscle. 10. Its tendon. 11. The continuation of the same into the 
palm of the hand. 12. The palmaris longus muscle. 13. The termination of its tendon in the annular ligament and palmar fascia. 
14. The tendon of the flexor carpi ulnaris muscle, which is seen running along the inner border of the fore-arm. 15, 15. The fleshy 
fibres of the superficial flexor muscle of the fingers ; the tendons of this muscle are drawn a little to the inner side in order to expose, 
17, the tendons of the deep-seated flexor muscles. 16. Part of the pronator quadratus muscle. 18. The anterior annular ligament 
of the wrist. 19. The palmar fascia. 20. Metacarpal bone of the thumb. 21. The small muscles of the little finger. 22. The 
abductor muscle of the index finger; the muscles of the thumb having been removed in order to expose it. Along the outer side of the 
fore-arm, extending from above the elbow down to the end of the radius, is seen the supinator longus muscle. At its upper part it is 
fleshy, but lower down it ends in a flat narrow tendon, which is inserted into the outer border of the radius, a little above its styloid 
process ; the point of attachment of the tendon is overlapped and concealed by the tendons of two of the abductor muscles of the thumb; 
between the tendon of the supinator muscle and that of the flexor carpi radialis, (10,) is 6een a part of the long flexor muscle of the 
thumb. 
Fig. 2, No. 1. The lower part of the humerus. 2. The inner condyle. 3. The inner side of the trochlea. 4. The olecranon process. 5. 
The superficial flexor muscle of the fingers. 6. Its tendons prolonged downwards to the palm of the hand. 7. The flexor carpi ulnaris 
muscle. 8. Its tendon of insertion; this muscle at its upper end presents two pointed processes by which it is attached to the inner 
condyle of the humerus, and the olecranon process of the ulna ; between these is an angular interval, through which passes the ulnar 
nerve ; some transverse fibres are observed to pass across from the one to the other. 9. The tendon of the abductor muscle of the 
metacarpal bone of the thumb. 10. The lower extremity of the radius. 11. The tendon of the long flexor muscle of the thumb. 
12. The lower extremity of the ulna. 13. The insertion of the tendon of the flexor carpi ulnaris muscle into the pisiform, or pea- 
shaped bone. 14. Part of the anterior annular ligament of the wrist. 



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will assist in drawing the fore-arm forwards, so as to place it in the flexed position. There is one case in which it may be even 
in the first instance a flexor muscle, viz. if the supinator muscles are previously put into action so as to prevent it from rotating 
the radius. Along the inner side of the muscle here noticed, lies another, which is considerably longer, as it extends from the 
inner condyle to the metacarpal bone of the fore-finger. The tendon, which is prolonged from its fleshy fibres, passes under the 
anterior annular ligament of the wrist, and slides through a groove in the trapezium bone, previously to reaching its insertion. 
It is called the radial, or outer flexor muscle of the wrist, (flexor carpi radialis,) not because it runs along the radial border of the 
arm, but merely from its direction towards the radial, or outer side of the hand, upon which it is made to act. The tendon of 
this muscle serves as the guide to the position of the radial artery in the ordinary operation of feeling the pulse at the wrist. 
Along the inner or ulnar border of the flexor radialis, lies a thin small muscle, which is prolonged to the annular ligament and 
palmar fascia, in which its tendon (13) terminates; hence it is termed palmaris longus: in many subjects it does not exist. Along 
the inner border of the fore-arm, and taking the direction of the ulna in its entire length, is placed the flexor carpi ulnaris muscle; 
its tendon, (No. 14,) and part of its fleshy fibres, are seen in fig. 1, but in fig. 2 it is fully shown ; its fleshy fibres (No. 7) proceed 
obliquely forwards from the ulna to reach the tendon, which lies along the fore part of the muscle. Its upper extremity is attached 
by two distinct points to the inner condyle and the olecranon process, in the interval between which the ulner nerve is placed, as 
it proceeds to the fore-arm. The superficial flexor muscle of the fingers is seen only at two points (15, 15) in fig. 1, as it is overlaid 
by the other muscles; but in fig. 2 it is brought more fully into view by their removal. At the outer border of the fore-arm is 
placed a long muscle, with a considerable fleshy body, which ends in a flat tendon ; it is called the long supinator of the radius, to 
distinguish it from another muscle possessed of a similar power, but which is deeply placed at the upper part of the fore-arm : 
underneath the long supinator are two extensor muscles, which are in great part concealed by it. 

Now, when we consider the power of these muscles, it is obvious that they can be made to act upon the bones of the fore- 
arm, the hand, and the fingers; the action of the pronator teres has been already noticed; the flexors of the wrist, as their name 
implies, can draw the hand forwards so as to bend it upon the fore-arm. The flexors of the fingers pull on their tendons like so 
many cords, and curve the joints so as to close the hand ; and having proceeded so far y they can be made to act upon the wrist 
too, and flex it upon the fore-arm. The pronator muscle is directly assisted in its action on the fore-arm, by a short square plate 
of muscular fibres stretched across from the radius to the ulna, close to their lower extremities: from its shape it is called pronator 
quadratus, by which it is distinguished from the other, which is named " teres," or round. The direct antagonists of the pronator 
muscles are the long and the short supinators, of which the former alone is seen in this plate ; the biceps muscle, it will also be 
recollected, has a similar power over the radius. 

The head of the radius may be displaced from its natural position, and thrown either backwards or forwards : of the latter 
dislocations Sir Astley Cooper met with six instances, but none of the former in the living subject. He had, however, an oppor- 
tunity of examining the state of the joint in the dead body of a man brought for dissection to St. Thomas' Hospital, in whom 
this dislocation existed, without being reduced, for a considerable time previous to his death. The coronary ligament was torn 

• 

PLATE XVII. 

The deep-seated muscles of the fore-arm and hand are here brought into view by the removal or displacement of the superficial set which 
conceal them. 

Fig. 1, No. 1. Internal condyle of the humerus. 2. The external condyle. 3. The fleshy part of the biceps muscle. 4. The brachialia 
anticus muscle projecting to the inner side of the biceps. 5. Part of the triceps extensor muscle. C. The insertion of the brachialia 
anticus into the coronoid process of the ulna. 7. The supinator radii brevis muscle. 8. The superficial flexor muscle; its attachment 
above is to the inner condyle of the humerus, lower down its fibres are fixed to the radius ; sometimes a pointed process, as here, is 
derived from the coronoid process of the ulna. 9. The tendons of the superficial flexor muscle, which are placed closely together, but 
diverge to their insertions after having got into the palm of the hand. 10. The long flexor muscle of the thumb. 11. Its tendon. 
12. A few fibres of the pronator quadratus muscle. 13. The flexor carpi ulnaris. 14. Its tendon. 15. The muscles of the little 
finger. 1G. The muscles of the thumb. 17. Its abductor muscle. 18. Part of the abductor of the index finger. 19. The sheaths 
which bind down the flexor tendons. 20. The sheath laid open in order to expose the tendon. 21. The tendon of the superficial 
flexor muscle at its insertion into the second bone of the fore-finger. 22. The tendon of the deep flexor muscle, alter having passed 
through the fissure and groove in the superficial flexor, is prolonged to the last bone of the finger. 

Fig. 2, No. 1. The inner border of the humerus. 2. The inner condyle. 3. The olecranon process. 4. Part of the brachialis anticus 
muscle. 5. The pronator radii teres muscle, which is here drawn forcibly out of its position, in order to show its two origins, and the 
interval between them; one being from the inner condyle, the other (No. 6,) from the coronoid process of the ulna. 7. Some fibres 
of the supinator radii brevis muscle. 8. The long flexor muscle of the thumb. 9. Its tendon. 10. The deep-seated flexor muscl 
the fingers. 11. Its tendons. 12, 12. The two extremities of the pronator quadratus muscle seen where t] I the 

preceding muscles. 13. The muscles which form the ball of the thumb. 14. Its abductor muscle. 15. The abductor of the index 
finger. 16. The muscles of the little finger. 17, 17, 17, 17. The sheaths which bind down the fl» \or tendons laid open and inverted. 
18. The tendon of the superficial flexor muscle remaining in its position. 19, 19, 19, 19. The tendons of the deep flexor m 
running on to their insertion into the last bones of the fingers. 
Musci.es. — 5 



34 

through at its fore part, the oblique one had also given way. The "capsular ligament was partially torn, and the head of Hie 
radius would have receded much more, had it not been supported by the fascia, which extends over the muscles of the fore-arm." 
Winn the arm was extended, the head of the radius could be seen as well as felt behind the external condyle of the os humeri. 
Professor Langenbeck, of Gottingen, met with two cases of this accident ; in one, a man twenty years of age, it was of six 
weeks' standing; in the other, a child five years old, it had occurred on the day previous to his admission into the hospital. The 
symptoms in both were so well marked, that the nature of the injury became manifest, even on the first inspection. The peculiar 
form of the radial side of the fore-arm, owing to the ulna not being displaced, indicated the nature of the mischief. At the origin 
of the supinator radii longus, and the extensors carpi from the external condyle, there was a marked prominence ; the outline of 
the arm was somewhat like that which exists in rickety persons, in whom the radius is generally bent. On examination of the 
joint, the head of the radius was found thrown backwards and outwards from the external condyle of the humerus, and could 
be immediately detected. The hand was prone, and could not be brought into the state of supination. The fore-arm was 
moderately bent, in which position it was fixed, for the arm admitted neither of flexion nor extension. At the inner side of the 
internal condyle the skin was loose, and presented a depression, in which the internal articulating surface could be felt. On 
tracing the radius from below, upwards, the finger came against the external condyle, behind which, in the adult, the articular 
surface only of the radius could be felt, and next to it the olecranon. When the finger was placed on this spot, and the radius 
was moved as far as it admitted, its motion was distinctly felt. In the other case, the glenoid cavity of the head of the radius 
could be felt behind and beneath the external condyle of the humerus. In the child, moderate extension only, with pressure on 
the end of the radius, sufficed for its reduction. In the adult, though the dislocation was of such long standing, it was reduced 
also. The " principal means to be adopted appeared to me, a powerful but gradual extension of the fore-arm, in order to draw 
the head of the radius towards the articulating surface of the humerus; at the same time making counter-extension at the 
upper arm, I pressed the dislocated head inwards. As in this case very strong and long-continued extension was necessary, 
I could, after a while, completely stretch out the fore-arm, which was before impracticable, and thus push the head of the radius 
inwards. The limb was kept in this situation by splints and bandages, and the patient was soon able to move the fore-arm in 
the four directions." — (Lancet, 1827, Vol. I. p. 248.) Though the extension was made from the fore-arm, in these cases it 
succeeded. In the first instances of the dislocation of the radius forwards which Sir A. Cooper met with, the efforts failed, even 
though long continued, as the force was expended for the most part on the ulna, which remained in its natural position. On 
considering the subject, it became obvious that this defect in the means of reduction could be remedied by making extension 
from the hand, for then all the force would be concentrated upon the radius. 

Boyer never metwith the dislocation of the radius forwards, and expresses doubts of its ever occurring. Sir Astley Cooper 
reports six cases of this form of accident. It was produced, at least in some of these, by a fall upon the hand with the arm 
extended ; the radius received, under such circumstances, the weight of the body, and was forced upwards and inwards so as to 
get in front of the coronoid process of the ulna. When this accident occurs, the fore-arm is slightly bent, but cannot be brought 
to a right angle with the upper arm, nor can it be completely extended. When it is suddenly bent, the head of the radius strikes 
against the fore part of the os humeri, and checks the motion. The hand is in the half-supine position. If the thumb be pressed 
into the middle of the bend of the elbow, the head of the radius can be felt, particularly if it be slightly rotated. " On dissection, 
the head of the radius is found resting in the hollow, above the external condyle of the os humeri ; the ulna being in its natural 
position. The coronary ligament of the radius, the oblique ligament, and the anterior ligament of the elbow joint, are torn 
through. The biceps muscle is shortened." — (On Dislocations, p. 440.) 



PLATE XVII. 

The first drawing in this plate shows the two pronator muscles of the fore-arm, and the short supinator, all the other muscles 
being removed, in order that the mode of action of those just named may be more clearly perceived. Having already noticed 
the pronator teres, and its action, it will suffice here to say, that it is assisted in the effort of turning the hand and fore-arm into 
the prone position by the flat square muscle placed immediately above the wrist, in close contact with the radius and ulna, No. 7; 
from its form and its action it is named pronator quadratus. The direction of its fibres is transverse, being extended outwards 
from the border of the ulna to that of the radius; when in action, they take their fixed point of attachment at the ulna, and then 
by drawing on the radius, they make it rotate upon the ulna as a fixed point, and so bring it and the hand into the prone 
position. 

The short supinator muscle, which is seen here, No. 3, is the direct antagonist, as its name implies, of the pronators ; its fixed 
points of attachment are the external condyle of the humerus, the external lateral ligament of the elbow-joint, and a ridge upon 
the posterior surface of the ulna. The fibres of the muscle arc directed, from these points downwards and forwards, lying close 



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upon tiie radius, to which they become inserted along an oblique line which extends from the bicipital tubercle down to the 
insertion of the pronator teres. When the hand and the fore-arm are placed in the prone position, this muscle, by means of the 
obliquity of its fibres, and by having its fixed points of attachment above and behind, is enabled to act on the radius, making it 
to turn upon its axis so as to pass from the prone to the supine position. It will be obvious, even from a cursory inspection of 
these muscles, that they must tend to displace the pieces of the radius in cases of fracture in that bone. When the accident 
occurs towards the upper part, the pronator will tend to draw the lower piece forwards, whilst the supinator carries the upper 
fragment somewhat backwards. If the fracture occurs at the lower part, the pronator quadratus, by reason of its transverse 
direction, approximates the bones when both are fractured, or draws the radius to the ulna when the former alone has suffered 
injury; and if this tendency on the part of the muscle be not prevented by placing the limb in a proper position, and by a careful 
adaptation of the fractured pieces, false anchylosis will be very likely to occur. 

The other figures in this plate exhibit the arrangement of the flexor tendons of the fingers, their points of attachment to the 
bones, their mutual adaptation the one to the other, the provisions devised for facilitating their movements by diminishing fric- 
tion, and for securing their power without increasing their bulk. The flexure, or bending of the different joints of the four 
fingers, is effected by means of two muscles (flexor sublimis and profundus,) which are seen in plate 17, fig. 1, No. S ; fig. 2, No. 
10. From each, four cords or tendons are prolonged into the palm of the hand, where they diverge a little from one another 
towards the fingers ; two tendons proceed to each finger, one derived from the superficial, the other from the deep flexor, both 
being in close contact, as seen in plate 18, fig. 8. As they run along the palmar surface of the bones of the fingers, they are 
retained in their position by a sheath of fibrous structure, which is stretched from one border of the finger bones to the other, so 
as to bind them down. When the sheath is cut open and reflected, as in fig. 7, so as to bring the tendons into view, that of the 
deep flexor will be found to run on to the last bone of the finger, whilst the superficial one is fixed to the second bone, fig. 6, 7, 
No. 6. The palmar surface of the first and second bones of each finger is slightly grooved, and in the natural condition of 
parts that groove is converted into a canal by the fibrous sheath above noticed, which is attached along the edges of the bones, 
and stretched over the two tendons, fig. 8 ; the fibres of this sheath are closely aggregated together, opposite the central parts or 
bodies of the bones, but towards their extremities, where they form the joints, the fibres become thin and scattered, so as not to 
impede or restrict motion. The surfaces of the tendons and of the sheath are lined by a synovial membrane, which secretes a fluid 
necessary to keep them at all times smooth and pliant. The contrivance adopted to permit the deep flexor tendon to pass beyond 

PLATE XVIII. 

Fig. 1, No. 1. The lower extremity of the os humeri. 2. The pronator radii teres muscle. 3. The supinator radii brevis. 4. The ulna. 
5. The radius. 6. The interosseous ligament. 7. The pronator quadratus muscle. 8. Part of the tendon of the supinator radii 
longus muscle. 9. The carpus. 10. The pisiform bone. 

Fig. 2. One of the tendons of the deep flexor muscle (flexor digitorum profundus,) detached from its connections so as to show its insertion 
into the last bone of the finger. No. 1. The flexor tendon. 2. The second bone, or phalanx of the finger. 3. The last bone of the 
finger. 4. The insertion of the tendon into its base. 

Fig. 3. No. 1. The deep flexor tendon seen at its posterior aspect. 2. The articulating extremity of the last bone of the finger. 

Fig. 4. One of the superficial flexor tendons, detached from its connections, so as to show the mode in which each of them is inserted into 
the second bone of the fingers, and also the fissure in its fibres, for the transmission of the deep flexor tendon. No. 1. A tendon of 
the superficial flexor muscle (flexor sublimis perforatus — m. flechisseur superficiel.) 2. The fissure through which the perforating 
tendon is transmitted. 3. The groove upon its palmar surface upon which the perforating tendon slides. 4. The second bone of the 
finger into which the perforated tendon is inserted by two pointed processes. 5. The third bone of the finger. 

Fig. 5. The perforated tendon detached from all its connections, as seen at its posterior aspect. No. 1. The tendon previous to its bifurca- 
tion. 2. The groove which it presents at its posterior surface, by which it is accommodated to the deep flexor tendon. 3. The fibres 
of the tendon united again, after having diverged to form the fissure. 4. Their ultimate subdivision into two pointed processes at their 
insertion into the second bone of the finger. 

Fig. 6. The two flexor tendons as they proceed to their points of insertion. No. 1, 2, 3. The first, second, and third bones of the finger. 
4. The metacarpal bone. 5. The perforated tendon of the flexor muscle. G. The deep, or perforating tendon. 7. The same continued 
onwards to its insertion. 

Fig. 7. The flexor tendons as seen when the sheath is laid open which binds them down in their situation; the references are the same as 
in the preceding. 

Fig. 8. Gives a lateral view of the flexor tendons and of their sheath. No. 1, 2, 3. The bones of the finger. 4. The metacarpal 
bone. 5. The fibrous sheath which binds down the flexor tendons. 6, 7. The superficial and the deep flexor tendons. 

Fig. 9. The flexor tendons are here shown as they pass from the fore-arm into the hand through the canal formed for them by the anterior 
annular ligament and the carpal bones. No. 1,2. The radius and ulna. 3. The interosseous ligament I. The anterior annular 
ligament cut through at its middle and drawn aside, the ends being held apart by hooks. 5. The pisiform bone. <">. Tin- metac 
bone of the thumb. 7. The metacarpal bone of the little finger. The flexor tendons form a cluster, and are in a manner compressed 
together under the annular ligament. Upon their surface rests a delicate synovial membrane, which is prolonged upwards and down- 
wards a little; upon them its points of reflection are distinctly indicated. 



36 

the superficial one deserves attention. The fibres of the latter separate into two narrow bands opposite the first bone of ihe 
finger, so as to leave between them an angular fissure ; they soon unite again (fig. 4, 5,) and proceed onwards, to be inserted by 
two pointed processes into the second bone of the finger. The deep flexor tendon, fig. 6, 7, No. 6, passes through the fissure 
here noticed, and is continued onwards to its insertion into the last bone. From this circumstance it is that they are called— the 
one, flexor perforatus ; the other, flexor perforans : this, however, is not all ; the superficial tendon is grooved at its posterior 
aspect, where it tonus the fissure, for at that point it rests upon the other tendinous cord, but farther on it is grooved upon its 
palmar or anterior surface, so as to accommodate itself to its new relation to the perforating tendon, which at this point lies 
upon it. 

I ig. 'J is intended to show the provision adopted for facilitating the movement of the flexor tendons, one upon the other. 
They are compressed closely together as they pass under the annular ligament of the wrist: in this situation, a thin synovial 
membrane invests them, capable of secreting a fluid which smoothens their surface ; it extends upwards and downwards a little ; 
the points of its reflection arc here distinctly seen: one membrane is common to the different flexor tendons of the fingers; the 
long flexor of the thumb has a synovial sheath distinct from the others. In order to expose the tendons and their synovial sheath, 
the anterior annular ligament is cut through at its middle, and reflected; this thick strong fibrous band is stretched across from the 
pisiform bone, and the projecting process of the unciform to the scaphoid and the trapezium; and after being fixed into the latter, 
some of its fibres are continued onwards, so as to form a sheath for the flexor carpi radialis muscle. Its upper border gives 
attachment to the fascia of the fore-arm; the lower gives attachment to the palmar fascia; from its anterior surface towards its 
inner border several of the fleshy fibres of the muscles of the little finger arise, and at its outer border some of those of the 
thumb. This ligament forms half a ring, or canal (the remaining half being made up by the carpal bones) of an elliptic form, 
which transmits the flexor tendons of the fingers and of the thumb, also the median nerve. 

The ulna may be dislocated by itself at the elbow joint, or at the wrist, without any displacement of the radius, notwith- 
standing the intimate connection which exists between these bones at their extremities, as well as along their shafts. When the 
sigmoid cavity of the ulna is separated from the trochlea, or pulley-like surface of the humerus at the elbow-joint, and when the 
radius still remains in its position, the fore-arm and hand arc much twisted inwards, giving rise to a considerable degree of 
deformity. The arm cannot be extended completely, nor can it be bent to more than a right angle. By tracing the line of the 
ulna from below upwards, the olecranon will be found prominent, behind the humerus, projecting higher up than its proper 
position; but the radius will be found before the external condyle of the humerus. These circumstances, taken together with 
the twisting of the arm inwards, will determine the nature of the accident. In a case of this sort, which had remained a long 
time unreduced before the death of the individual, the coronoid process of the ulna was found on dissection to have been lodged 
in that pit at the back part of the humerus which receives the olecranon when the limb is extended; the olecranon projected 
considerably behind the humerus; the radius was in a manner hitched upon the external condyle of the humerus, where a new 
joint was formed for it, which admitted of some rotatory motion; the orbicular and oblique ligaments were ruptured, and also 
some fibres of the interosseous ligament. The brachials anticus muscle was stretched over the extremity of the humerus ; the 
triceps was of course relaxed. This dislocation may be reduced by resorting to the expedient which is practised in cases of 
dislocation of both bones backwards, viz. that of bending the arm over the knee, and drawing the fore-arm downwards. As 
soon as the coronoid process of the ulna is dislodged from the fossa into which it is thrown, the brachialis anticus muscle will 
direct the bone into its proper position. 

The lower extremity of the ulna may be separated from the radius, and be thrown either backwards or forwards. Most 
writers now agree in considering this accident as a dislocation of the ulna, though it arises from a twisting of the radius, and the 
force which produces it is applied to the latter bone, or to the hand, causing in effect a displacement of the radius from the ulna. 
In cases of dislocation of the lower end of the ulna backwards, which more frequently occurs than that in the opposite direction, 
the fore-arm and hand are in a state of forced pronation, the shaft of the radius instead of being in a line with that of the ulna, 
crosses it in front at an acute angle, so that the breadth of the fore-arm at its lower part is much diminished ; the fore-arm and 
the hand are somewhat flexed, and the tendons of the flexor muscles pressed inwards present a peculiar appearance along the 
inner side of the radius, and the lower end of the ulna forms a considerable prominence at the back of the hand, so that it is no 
longer on a level with the cuneiform bone, nor is its styloid process in a line with the metacarpal bones of the little finger. In 
the dislocation forwards the same sort of narrowing of the limb and crossing of the bones exist, but in a less degree ; the ulna is 
on a plane anterior to the radius, the fore-arm and hand are necessarily placed in a state of fixed supination ; the flexor tendons 
are pressed outwards, and the lower extremity or head of the ulna forms a prominence at the fore part of the wrist. This dislo- 
cation has been caused from a violent twist, or a wrenching movement given unexpectedly to the hand, by which it is turned 
outwards suddenly into the supine position. The pain, the deformity, the position of the limb, and the projection of the ulna, 
leave no doubt as to the nature of the accident. The dislocation backwards maybe produced by a sudden wrenching or twisting 
movement in the opposite direction, by which the hand and fore-arm arc brought into the state of forced pronation. It occurred 
in this way to a laundress, whose case Desault has recorded. She was engaged in wringing or twisting clothes with another 
Woman, and whilsl in t' twisted the wrist so violently forwards as to produce the luxation of the head of the ulna back- 



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37 

wards. The accident may also be produced by a force applied to the hand whilst falling. Boyer gives the dissection of a case 
of dislocation of the end of the ulna forwards, which had remained unreduced for some time before the death of the individual. 
In front of the lower part of the fore-arm a hard prominence was observed, and a depression at the opposite point. This attracted 
attention, and suggested the expediency of examining it carefully. The hand was oedematous ; the flexor tendons were pressed 
outwards, and had become adherent to one another and to the skin ; the sigmoid cavity of the radius was filled up by a new 
deposit, occupying the place of the cartilage which naturally covers it ; the triangular fibro-cartilage which connects the radius 
with the ulna was torn from the latter bone, and accompanied the radius in its movement backwards ; the head of the ulna lay on 
a plane anterior to the sigmoid cavity of the radius, and rested upon a sesamoid bone, with which it was connected by a capsular 
ligament. In attempting the reduction of these dislocations, it is necessary, in the first place, to lessen the pressure which the 
end of the ulna makes against the radius, before any attempt is made to force it in its proper position. The patient being placed 
sitting on a chair, an assistant steadily supports the fore-arm, and another the hand ; the surgeon then placing himself at the out- 
side of the limb, takes hold of its lower part with both hands, placing them in such a way upon it that the thumbs shall meet at 
the interosseous space, and at that side of it towards which the dislocation has occurred, viz. in front, where the dislocation of the 
ulna has taken place forwards, and vice versa. He then makes an effort to draw the bones in opposite directions, as if with a 
view to separate them from one another ; and as soon as he finds them to give way a little, the assistant who holds the hand 
endeavours to turn it into the supine position, in the case of dislocation backwards, whilst the surgeon presses the head of the 
bone with both his thumbs forwards. When the bone is dislocated forwards, the same plan is followed ; the movements, with a 
view to its restoration, being made in the opposite direction. 

The radius and ulna may be displaced from their connection with the carpal bones in either of four directions, viz. back- 
wards, forwards, or laterally to either side. The first two occur much more frequently than the others, which is partly owing to 
the circumstance that the extent of articulating surface is less from before backwards than from side to side, but chiefly because 
the greater number of efforts which we make, tend to throw it backwards or forwards, and not inwards or outwards : owing to this 
latter cause, and also to the extent of the articular surfaces in the transverse direction, the lateral dislocations are almost always 
incomplete. When in falling, a person puts out his hand to save himself, and strikes with the palm against any resisting body, tho 



PLATE XIX. 

The first and second planes of muscles, situated at the back of the fore-arm and hand, are seen in these drawings. The outline of the limb 
is traced by a line indicating the section of the skin, with a view to render its appearance more natural. 

Fig. 1, No. 1. The olecranon process of the ulna. 2. The external condyle of the humerus. 3. The triceps extensor muscle, (its tendon 
into which the fleshy fibres are seen to pass obliquely backwards.) 4. Part of the flexor muscles — the biceps and brachialis anticus. 
5. The long supinator muscle, (supinator radii longus.) 6. The long radial extensor muscle, (extensor carpi radialis longior.) 7. 
The short radial extensor muscle, (extensor carpi radialis brevior.) 8. The anconeus muscle. 9. The internal or ulnar flexor muscle 
of the wrist, (flexor carpi ulnaris:) its attachment by aponeurotic fibres along the inner border of the ulna is here shown. 10. The 
lower part of the ulna. 11. The lower part of the radius. 12. The common extensor muscle of the fingers, (extensor digitorum 
communis.) 13. The extensor muscle of the little finger, (extensor digiti minimi.) 14. The inner or ulnar extensor muscle of the 
wrist, (extensor carpi ulnaris.) 15. The long abductor muscle of the thumb, or the extensor of its metacarpal bone, (extensor ofisrB 
metacarpi pollicis.) 16. The shoit extensor of the thumb, or the extensor of the first phalanx, (extensor primi internodii pollicis, 
seu, extensor minor pollicis manus.) 17. The tendon of the long extensor of the thumb, (extensor major pollicis manus,) in the fore- 
arm it is covered by the common extensor muscle of the fingers. 18. The tendons of the two muscles of the thumb (15, IG) running 
together along the outer border of the wrist. 19. The tendon of the short radial extensor at its insertion into the third metacarpal bene. 
20. The tendon of the long radial extensor muscle at its insertion into the second metacarpal bone. 21. The tendons of the exft nsoi 
muscle of the fingers as they are passing down towards the back of the wrist. 22. The posterior annular ligament of the wrist 
stretched over the extensor tendons, and binding them down in their proper situations. 23. The abductor muscle of the forc-fingor. 
24. The insertion of the abductor muscle of the thumb. 

Fie. 2, No. 1. The lower part of the arm-bone — os humeri. 2. The posterior fibres of the brachialis anticus muscle brought into view by 
the removal of the triceps extensor, as seen in fig. 1, No. 3. 3. The anconeus muscle. 1. The short radial extensor muscle; the 
long radial extensor, and the long supinator, as seen in fig. 1, No. 6, 7, being removed in order to show it more fully. 5. The short 
supinator muscle, (supinator radii brevis.) 6. The long abductor of the thumb, or the extensor of its metacarpal bone. 7. The extensor 
of the first bone (phalanx) of the thumb. 8. The long extensor of the thumb, or the extensor of its second bone, (phalanx.) 9. The 
extensor of the index finger. 10. Part of the flexor ulnaris muscle seen arising from the inner condyle of the humerus, and running 
along the inner border of the arm to reach the fore part of the wrist: its origin from the olecranon process and its aponeurotic attach- 
ment along the inner border of the ulna are removed, in order to bring into view No. 11, the deep flexor of the fingers, the fihr 
which are seen attached along the inner side of the ulna. 12. A small part of the tendon of the extensor carpi ulnaris muscle, left at 
its insertion into the fifth metacarpal bone. Close to it is seen the groove which transmits the tendon of the extensor of the little finder. 
13. The insertion of the adductor muscle of the thumb. 14. The external origin of the abductor muscle of the fore-finger — between 
it and the oilier part which is attached along the metacarpal bone of the fore-finger, is seen an angular interval, which transmits the 
radial artery as it passes to the palm of the hand. 



38 

rounded surface formed by the bones of the carpus is made to slide from behind forwards, so as to press against the anterior 
ligament of the wrist joint. If the force be considerable, the ligament will give way, and the carpal bones will be pressed for- 
wards, so as to get before the lower extremity of the radius. In this case the hand inclines backwards, being iu a state of 
unnatural extension: but the fingers are flexed. The carpus forms a marked projection at the fore part of the wrist, whilst at 
the hack part there is a transverse depression or crease, corresponding with the lower end of the radius. The projection of the 
carpus renders the flexor tendons tense, and gives rise to the bending of the fingers. If the force of the fall is by any circum- 
stance made to act upon the back of the hand, then the carpal bones will be made to glide from before backwards upon the 
articular surface of the radius, so as to press against the posterior radio-carpal ligament, and to rupture it. The carpus is thus 
thrown behind the bones of the fore-arm, constituting the dislocation backwards. In this case the hand, or rather the metacarpus, 
is drawn forwards or flexed, whilst the fingers are in the extended position. The carpus is very prominent at the back part of 
the joint, whilst at its palmar aspect there is a transverse depression or crease, corresponding with the lower border of the radius 
and ulna; the projection of the carpus forces back the extensor tendons, and renders them tense. There is seldom much difficulty 
in reducing these dislocations, and the mode of proceeding is the same, no matter in what direction the displacement has occurred. 
The fore-arm is placed in the flexed position, an assistant takes hold of the upper arm firmly with both hands just above the 
elbow, the surgeon then seizes the patient's hand and makes a steady extension, the assistant keeping a counter-extension, so 
that the bones of the fore-arm and hand are drawn in opposite directions. As soon as they cease to overlap, the one the other, 
the muscles will give the displaced part its proper direction, and draw it into its natural position. 

PLATE XX. 

The drawings in this plate give different views of the hand, the skin and fascia being removed in order to exhibit the muscles more distinctly. 

Fig. 1. The back of the hand. 

No. 1. Part of the ulna. 2. The lower part of the radius. 3. The posterior annular ligament of the wrist joint. 4. The long abductor 
muscle of the thumb. 5. The extensor of the first phalanx of the thumb. 6. The tendon of the extensor of the second phalanx of 
the thumb. 7. The tendons of the common extensor muscle of the fingers, (extensor communis digitorum.) 8. The tendon of the 
extensor muscle of the little finger. 9. The tendon of the extensor ulnaris muscle. 10. The tendon of the long radial extensor 
muscle, (extensor carpi iadialis longior,) at its insertion into the second metacarpal bone. 11. The tendon of the short radial extensor, 
(extensor carpi radialis brevior,) at its insertion into the third metacarpal bone. 12. The first dorsal interosseous muscle. The other 
three muscles of this name are seen in the greater part of their extent in the interstices between the extensor tendons. 

Fig. 2. The muscles of the palm of the hand as seen when the palmar fascia is removed. 

No. 1. Part of the fascia of the fore-arm. 2. The tendon of the flexor ulnaris muscle. 3. The tendon of the flexor carpi radialis muscle. 
4. The palmaris longus. 5. The palmaris brevis. G. The abductor muscle of the little finger. 7. The short flexor of the little 
finger, (Hew brevis minimi digiti.) 8. The short abductor muscle of the thumb. 9. The short flexor muscle of the thumb. 10. 
The insertion of the opponens pollicis muscle along the margin of the metacarpal bone of the thumb. 1 1. The tendinous sheath which 
binds down the tendon of the long flexor muscle of the thumb. 12. The first dorsal interosseous muscle, called also the abductor of 
the index finger. 13. Part of the adductor muscle of the thumb. 14. Is omitted. 15. The first lumbricalis muscle. The other 
muscles of this name are seen passing forwards from the flexor tendons towards the margins of the first bones of the fingers, and be- 
coming tendinous as they are inserted into the edge of the extensor tendon of each finger at its radial border 16. The commencement 
of the fibrous sheath which binds down the flexor tendons. 

Fig. 3. The second plane of muscles in the palm of the hand. 

No. 1. The pisiform bone. 2. The lower extremity of the radius. 3. The anterior annular ligament of the wrist joint. 4. The origin 
of the short abductor muscle of the thumb. 5. Its insertion, the intervening part being cut away in order to expose the subjacent 
muscle. 0. The short flexor muscle of the thumb. 7. The opponens of the thumb. 8. The tendon of the long flexor muscle of the 
thumb passing en to its insertion into the base of its second phalanx. 9. The adductor muscle of the thumb. 10. The abductor of 
the index finger, or first dorsal interosseous muscle. 11. The abductor muscle of the little finger. 12. The short flexor of the little 
finsrer, (flexor brevis digiti minimi.) 13. 'I 'he tendons of the deep-seated flexor muscle of the finger, (flexor profundus perforans.) 
passing on to their insertions into the last phalanges of the fingers. To expose these, the tendons of the superficial flexor muscles are 
cut across as they emerge from under the annular ligament of the wrist, and also opposite the first joints of the fingers, and the inter- 
vening part taken away. This brings into view the deep flexor tendons in the palm of the hand, and also their accessories, viz. the 
four lumbricales, which are four tapering fasciculi that arise from the tendons of the flexor muscle, and proceed forwards to be inserted 
into the borders of the extensor tendons. 

Fig. 1. Shows the third plane of muscles in the palm of the hand. The flexor muscles and their tendons, and the superficial muscles of 
the palm of the hand, are removed in order to bring those which are deep-seated into view. 

No. 1. The pronator quadratus muscle. 2. The opponens muscle of the little finger. 3. Part of the tendon of the flexor carpi radialis 
muscle. 4. The tendon of the flexor carpi ulnaris muscle. 5. The opponens muscle of the thumb. 6. The sheath for the tendon 
of the flexor longus pollicis muscle, which partly conceals the tendon of the broad triangular muscle (adductor pollicis) converging 
towards it from the metacarpal bone of the middle finger. 7. Part of the first dorsal interosseous muscle. 8. The first palmar inter- 
osseous muscle. 9. The second dorsal interosseous muscle. 10. Tho third dorsal interosseous muscle. 11. The second palmar 
interosseous muscle. 12. The fourth dorsal interosseous muscle. 13. The third palmar interosseous muscle. 14. Some of the fibres 
of the sheaths of the tendons left on in order to retain the tendons in their positions; they are drawn a little too strong. 



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In cases of dislocation inwards, the carpus forms a projection towards the inner side of the joint, beneath the inferior 
extremity of the ulna ; the outer edge of the hand is inclined towards the radial border of the fore-arm, as if in the state of 
forcible abduction. In the dislocation outwards, the carpus becomes prominent beneath the lower extremity of the radius, and 
the inner border of the hand is drawn towards the ulnar side of the fore-arm, so as to be placed in a state of forced adduction 
These displacements being incomplete, are easily reduced; the plan above indicated in the cases of the other two dislocations 
will suffice for them. 



PLATE XIX. 

The muscles placed at the back part of the fore-arm and hand are here exhibited, the skin and fascia which bind them down 
having been removed in order to show more distinctly their relative position and points of attachment. They are divided into 
two sets, one of which is superficial in its entire extent, and overlays the others, so as wholly or in part to conceal them. The 
superficial set consists of the anconeus, the common extensor of the fingers, the extensor of the little finger, and the inner or ulnar 
extensor muscle. The deep-seated set consists of the long abductor and the two extensors of the thumb, the extensor of the 
index finger, and the short supinator muscle. 

At the back part of the elbow is seen a small flat triangular muscle, No. 8, fig. 1 ; No. 3, fig. 2 ; it is termed anconeus from 
its position. It commences by a narrow tendon attached to the back part of the outer condyle of the humerus, the fibres of 
which are prolonged for some way along the outer border of the muscle. From these the fleshy part of the muscle arises, and 
the fibres of which it is composed will be seen to spread out as they proceed backwards and inwards to be inserted into the outer 
side of the olecranon process of the ulna, and into the posterior border of the ulna for a little way farther down ; the upper fibres 
of the muscle are very short and nearly horizontal in their direction, but those which succeed them gradually increase in length. 
It is on the same plane with the triceps extensor muscle, fig. 1, No. 3, of which it often appears to be a continuation, and with 
which it conspires in its action upon the fore-arm, viz. in extending it so as to bring it into a right line with the humerus. 

The common extensor muscle of the fingers, fig. 1, No. 12, extends from the external condyle of the humerus to the extremi- 
ties of the fingers. It presents a rounded fleshy body, a narrow pointed commencement or origin, and at the middle of the fore- 
arm a tendinous prolongation, which soon branches out into four flat bands, which, after passing under the posterior annular 
ligament of the wrist, proceed along the back of the hand to reach the first joints of the fingers, over which they are continued 
uninterruptedly ; whilst passing behind the first bones of the fingers, they receive the insertions of the interossei and lumbricales, 
which increase their breadth, and give them the appearance of broad aponeuroses covering the back part of the fingers. Near 
the second joint of each finger the fibres of the tendon appear to separate, so as to leave an elliptic interval between them; this 
is owing to the fact, that the fibres at the side are comparatively thick and strong, whilst the middle part is thin where it slides 
behind the joint, and becomes inserted into the extremity of the second bone of the finger ; this arrangement of the tendon is calcu- 
lated to facilitate the bending of the joint, for the knuckle is received in the interstice between the diverging fibres of the tendon. 
Further on, the parts of the tendon become united again into a flat band, which is inserted into the last bone of the finger ; the 
tendon of the ring finger is observed to be connected with that of the middle one by a transverse slip, which passes from the one 
to the other ; a similar connecting band passes off to the tendon over the little finger. In the present instance, the tendon for the 
little finger is but a small slip, formed of a few fibres which run along the margin of the tendon of the ring finger, and merely 
forms part of the oblique slip or connexion already noticed, but which here passes to the proper extensor of the little finger. 
This muscle is the direct antagonist of the flexors of the fingers, which are placed at the fore part of the limb, for it extends the 
bones of which they are composed, so as to bring them into the straight position, and when it has carried the fingers as far back 
as they will admit of, it can continue its action so as to extend the hand upon the fore-arm. 

The proper extensor muscle of the little finger is a long and narrow slip, which lies along the ulnar border of the common 
extensor muscle, with which its fibres are united in a considerable part of their extent. From the external condyle it stretches 
down the middle of the fore-arm, and ends in a tendon, No. 13, which after passing under the posterior annular ligament of the 
wrist is continued over the fifth metacarpal bone, and finally, after becoming blended with the fourth tendon of the common 
extensor muscle, it is continued over the bones of the little finger, having the same relation and connexions with them which 
the other extensor tendons have, and like them it is inserted into the base of the last phalanx. The ulnar extensor muscle, No. 
14, extends from the outer condyle of the humerus to the upper extremity of the fifth metacarpal bone ; some of its upper fibres 
are attached to the fascia of the fore-arm, and an aponeurotic band between it and the common extensor muscle ; and below the 
anconeus it also has attachments to the posterior surface of the ulna. The tendon into which its fibres run passes through a 
groove appropriated to it in the annular ligament, previously to its insertion into the fifth metacarpal bone, fig. 2, No. 12. This 
muscle, when in action, can extend the hand upon the fore-arm, and incline it towards the inner or ulnar side. 

The muscles which we have here noticed, partly conceal from view those which lie immediately upon the bones and intcros- 



m 

scous ligament, and which form the second plane. These are shown in their entire length in fig. 2, the superficial set being 
removed. The fibres of the short supinator of the radius, No. 5, represent a flat triangular plane, extended obliquely over the 
outer border of the radius. It has been already noticed in our comment on Plate XVIII. Immediately beneath its lower border 
is sen the long abductor muscle of the thumb, No. 6 ; its direction is obliquely downwards and outwards from the ulna, across 
the interosseous ligament and the radius, to both of which its fibres are attached. In this part of its extent it represents a rounded 
fleshy fasciculus, which at the lower part of the arm ends in a flat tendon, which after passing through a groove upon the outer 
border of the radius is fixed to the upper extremity of the metacarpal bone of the thumb ; hence it is frequently called the 
extensor of the metacarpal bone. At its lower border, and partly concealed by it, is placed the extensor of the first bone of the 
thumb, No. 7, which is shorter and smaller than the preceding; its fibres are attached to the interosseous ligament and radius, 
and take the same oblique direction from above, downwards and outwards, to end in a narrow tendon which runs through the 
same groove in the radius that transmits the tendon of the extensor of the metacarpal bone, and is thence continued onwards to 
be inserted into the base of the first phalanx of the thumb. The extensor of the second bone of the thumb, No. 8, also runs an 
oblique course, but its tendon is separated by an interval from the preceding, and slides in a groove appropriated to itself at the 
back part of the radius. Its fibres arise from the middle third of the ulna and from the interosseous ligament, and the tendon in 
which they terminate, after passing through the groove in the radius just noticed, slides over the insertion of the two radial 
extensors, (fig. 1, 19, 20,) and is prolonged upon the dorsal surface of the thumb to the base of its last phalanx, into which it is 
inserted. Still lower down, and on the same plane, lies the extensor of the index finger, No. 9 ; its fibres are attached to tlie 
posterior surface of the ulna and the interosseous ligament. The tendon in which its fibres terminate will be found in the groove 
which transmits the common extensor muscle, and as it passes along the back of the hand it is in close contact with the band 
given by the common extensor to the index finger, with which it becomes identified. 

The tendons of the extensor muscles, whilst running along the back of the hand, overlay and partly conceal from view 
some small muscles, which are deeply seated, inasmuch as they lie in the intervals between the metacarpal bones, from which 
circumstance they are termed the interosseous muscles. In order to bring them fully into view, the extensor muscles, with their 
tendons, are cut across over the first joints of the fingers, fig. 2, and removed, and the tendon of the indicator muscle is drawn 
slightly out of its place. There are four interosseous spaces, each of which at the dorsal aspect of the hand is occupied by a 
muscle. At the palmar aspect there are three, the tendons of which are here slightly seen as they are prolonged from the palm 
in the second, third, and fourth interosseous spaces, to be inserted into the margins of the extensor tendons. The first dorsal 
interosseous muscle is the largest of the set, and occupies the interval between the metacarpal bone of the thumb and that of the 
fore-finger ; its fibres arise from the contiguous margins of these two bones, and at first appear as two bundles separated by ;in 
angular interval, but as they proceed forwards, each approaching the other, they unite and form a flat narrow muscle, and this 
ends in a tendon which is inserted into the base of the first bone of the fore-finger, and is also connected with the outer margin 
of the tendon over that finger ; from its line of direction it is obvious that this muscle can draw the fore-finger away from the 
rest, on which account it is called the abductor of the index finger. The second and third dorsal interosseous muscles arise from 
the contiguous margins of the metacarpal bones, between which they lie ; they also consist of oblique fibres, which converge 
towards a middle line ; each ends in a narrow tendon, which is inserted into the margin of the extensor tendon, lying over the 
middle finger. These, when in action, can incline the finger laterally ; the one drawing it inwards, the other outwards. The 
fourth dorsal interosseous muscle, similar in structure and mode of origin to the preceding, is inserted along the inner or ulnar 
side of the extensor tendon of the ring finger. 



PLATE XX. 

The drawings here given exhibit different views of the hand placed in the position in which it is usually examined by the 
anatomist. The skin and fascia are removed in order that the form, the lines of direction, and the points of attachment of the 
muscles may be distinctly seen. What a number of objects are here grouped together in a small space ! the bones which form 
the substratum that gives support to the rest vary much in form and size, so do the muscles which move them, and their number 
is proportioned to the variety of motions which the hand can perform. In every part of the body, evidence of design and 
contrivance may be traced ; in none is it more clearly demonstrable than in the hand, and the demonstration may be rendered 
more complete were we to extend our observation to the whole limb of which it forms a part. Observation shows us how well 
adapted it is for its different purposes and uses, and how infinitely various these are. Let us contrast it with the lower extremity: 
placing them side by side, we see that the parts of which they are composed, I mean the anatomical elements of which they are 
made up, are analogous in every particular. Just take the basis, or substratum, which gives support to the other structures,— 
the osseous part: laying them thus together, (fig. 1, 2,) we see that they consist of the same number of pieces, viz. the femur (a,) 
and humerus (a*,) the two bones (c, d,) of the leg, and those of the fore-a-m (r\ d\) the different pieces in the tarsus (e) and 



41 



carpus (<»*,) those of the metatarsal row (/,) and in the meta-carpus (/*,) and lastly those of the toes (g,) and of the fingers (g*.) 
The femur, strongly made, is, at its upper part, lodged in a deep cup-shaped socket, by means of which the whole weight of the 
body is thrown on the limb ; at its lower end it is expanded so as to increase the surface by which it rests on the leg. The bones 
of the leg are also firm in themselves, and closely bound together so as to admit of no motion upon one another ; they rest 
securely on the foot, the upper bone of which is lodged in a socket, which they form. The humerus, on the contrary, is barely in 
contact with a superficial depression on which it moves, and so admits, at the shoulder, the utmost variety and latitude of move- 
ment ; the bones of the fore-arm, too, are calculated for flexibility and motion, one rolling on the other, and both fitted with a 
perfect apparatus of muscles or moving powers, which, with the utmost ease and precision, turn the wrist, and guide the hand 
to any object to which it is to be applied. The bones, then, in arrangement and general plan, are similar, yet, by slight modifi- 
cations, are fitted for totally different purposes. 

The hand and the foot (2, 1,) agree in the elements of which they are composed, and in the number of them; but they are 
developed so differently in each, that they form totally distinct members, and serve for widely different purposes. The solid and 
the moveable parts in each are strongly contrasted; the pieces which compose the solid part of the foot (fig. 1,) are strong and 
large, those of the hand (2,) are comparatively diminutive, but the fingers, or flexible part, are largely developed, as compared 
with the toes. It is commonly said that this arises merely because the toes are less necessary for support and progression than 
the rest of the foot, whilst the fingers are more necessary for prehension and adjustment than the rest of the hand; it would be 
more correct to say that it is the result of a general law which pervades the whole animal kingdom, a law which eslablisln -s 
what may be termed a principle of compensation, by virtue of which, if any given part is increased above par, its increase is 
effected at the expense of some other; or, as it has been technically expressed, if the "formative effort" be strongly directed to 
one part, it will be less so to some neighbouring one. The arch of the foot is the more important part in reference to its general 
purpose of sustaining the body, the toes being obviously less so as a means of support or progression. It is just the reverse in the 
hand : the fingers, or flexible part, being the more important one, in reference to the various purposes which the hand has to 
perform, and therefore they are proportionally evolved or developed. 

Again, when we direct our attention to a single part of the hand, viz. 
the thumb, and contrast it with the corresponding part of the foot, we see 
how a new instrument is produced by a mere modification of its constit- 
uents. The bones, the muscles, vessels, and nerves of the thumb, and of 
the great toe, are respectively analogous, yet how different are the purposes 
which they are intended to fulfil ? The first bone of the toe is thick and 
strong, it ranges with those of the other toes, and admits of little more 
motion than they do, as it is one of the chief points on which the weight 
of the body is thrown in its different movements. The first bone of the 
thumb admits of every variety of motion ; it does not range with those of 
the fingers, from which arises its most striking peculiarity, that of being 
brought into opposition with the rest. In its various uses it is not merely 
a part of the hand, — it is rather a new member, or a supplemental hand. 
Thus we see what a variety of results are obtained from a few materials, 
and how, by a modification in the form, proportion, and arrangement of 
the same constituents, new instruments are produced, — new powers 
created. 

But let us not confine our attention to the structure of the human frame, 
let us glance at that of other animals, still for illustration, confining our 
attention to the instance already selected, viz. the upper or anterior ex- 
tremity : take that in one of the lower animals, say the cat. Ordinarily it 
sustains the body, therefore, is an instrument of support ; its parts move on 
one another, and, when acted on by the muscles, it becomes an instrument 
of progression ; it is terminated by moveable phalanges, which may be 
flexed or extended, and so it becomes a means of prehension ; finally, the 
last phalanges, which are usually turned back, may be pushed forward to 
a line with the rest, protruding the sharp nails with which they are armed, 
and so it becomes an instrument of attack or defence. In the monkey this 
limb serves for support and progression, but chiefly for the prehension of 
objects ; it is not well calculated for defence or attack. In (he dog and in 

hoofed animals it serves for support and progress ; in birds for progression only ; whilst in fishes is merely assists in progression, 
as that is effected chiefly by the movement of the hinder part of the body. Now, in the anterior limb in all these . we 

Muscles. — G 




42 

find the same bones, muscles, nerves, vessels, &c. ; and all the variety of purpose which they serve is attained by modification 
in the size, form, and mode of connexion of these components.* We often speak of the simplicity of Nature's works here that 
simplicity is fully exemplified. These limbs consist of the same parts, — the materials are identical ; yet, as we have seen, thev 
execute different functions, and so may be considered as different organs, which is sufficiently indicated by the different names by 
which they are popularly known. And all this is effected by one portion being largely developed, a contiguous one bein°- less 
so, — some being evolved to a maximum, whilst others are left rudimentary, as if Nature were sparing of her materials, yet 
profuse in the results she would elaborate out of them : and this is what we really mean when we speak of the simplicity of 
Nature's works, as contrasted with the grandeur and comprehensiveness of her designs. 

When we have inspected attentively the leading divisions of the animal kingdom, and examined the structure of its different 
orders, say from the fishes up to the mammalia, we see that, though variously modified, the proximate or anatomical constituents 
of the members, (as in the instances cited,) and also of the trunk, are analogous. Now, whilst we pass from link to link in this 
great chain, if the mind dwells sufficiently long on each of the natural families which it connects to retain an impression of its 
fundamental form, omitting the minor traits which give to each its individuality ; if, in a word, as it passes from the lowest to the 
highest, it retains that which is essential in the form and composition of each, abstracting its peculiarities, it will gradually ascend 
to the contemplation of a form, which will be a type, or representative of all, divested of the peculiarities which mark each of 
them. Having thus ascended to the contemplation of a type, or abstract form, which may be conceived to contain within it the 
components, or anatomical elements, of each of the great classes (fishes, reptiles, birds, mammalia,) and retaining it for a while 
before the mind's eye, so as to fix the impression of it, we may readily reverse this process, and proceed to evolve the model 
which is thus present to the mind, and give to each limb, as well as to the body, such a degree of expansion or development as 
will make it represent the form which it presents in a fish, a reptile, a bird, or a quadruped. Thus, for example, the structures 
of the anterior extremity whilst in their rudimental state, are found aptly enough at the bottom of the scale in form of ihe fishes' 
fin. (In fig. 7, a represents the bones of the shoulder; b, c, the radius and ulna ; d, the fin-rays, being so many digital processes.) 
We find the osseous structure very perfect in the limbs of the amphibia. In the ophidian reptiles it does not exist, but in the 
sauria and batrachia it is variously modified, to suit the habits of these animals. In the class of birds it is developed considerably 
to form the wing ; fig. 6 shows part of the wing of a bird ; a, the humerus ; b, the radius ; c, ulna ; d, carpus ; e, metacarpus ; 
1,2, the great finger, — its two phalanges. And the same elements, by receiving their appropriate adjustment, are made to 
represent the limb as it is in the solidungula, (fig. 5 ;) in the bisulca, (fig. 4 ;) in the feline tribe, (fig. 3 ;) and finally the hand of 
man, (fig. 2.) Having thus sketched a part in each, we may, by a similar process, complete the figure by following it out through 
the posterior extremity, and then the body, spine, and head ; the parts of the skull being analogous to vertebrae. It is in this 
way only that we can form any adequate conception of the plan or groundwork from which the different varieties of animal 
forms are deduced. For, when we look over a menagerie, or a great assemblage of animals, our first impression is that of variety 
and discrepancy; but, on a closer inspection, we find that some are nearly allied, and form groups or families, marked by certain 



PLATE XXL 

This drawing exhibits the first layer or plane of muscles placed along the back and side of the body; the skin and the cellular tissue being 
removed in order to show the direction of the fibres in each muscle, and their points of attachment. 

No. 1 . The protuberance of the occipital bone. 2. The mastoid process of the temporal bone. 3. The acromion process of the ri»ht 
scapula. 4, 4. The spinous processes of the two scapulae. 5, 5. The base of each scapula. 6, 6. The margins of the iliac bones. 
7. The sterno-cleido-mastoid muscle. 8. Part of the splenius as seen between the margin of the preceding and of the trapezius. 9. 
Part of the levator scapulae. 10, 10. The trapezius muscle of each side; and as it is of very considerable extent, forming a flat angular 
plane which extends from the occiput to the spinous process of the last dorsal vertebra ; the numbers 10, 10, are repeated in the lower 
part of it. 11, 11. The latissimus dorsi muscle of each side, which is also of considerable size. 12. The external oblique muscle 
of the abdomen. 13. Part of the border of the great serratus muscle, presenting angular points interposed between the fibres of the 
external oblique muscle. 14. A part of the lower border of the great pectoral muscle where it forms the anterior fold of the axilla. 
15. The teres major muscle. 16. The teres minor muscle. 17. The infra-spinatus muscle. 1 8. A small part of the greater rhomboid 
muscle. 19. Some of the fibres of the longissimus dorsi muscle which are deeply seated, and exposed only when the scapula is 
drawn forwards, as here exhibited. 20. The deltoid muscle. 21. Part of the upper extremity of the brachialis anticus muscle where 
it arises below the insertion of the deltoid. 22. The long head of the triceps extensor muscle of the arm. 23. Its external or middle 
head. 

* The expression in the text must be taken with some limitation. For even in the fore foot of a monkey, so analogous as regards structure in other 
respects to the human hand, there is one very important muscle wanting, which belongs to man, the flexor longus pollicis. Iris this muscle which, acting 
separately, places the thumb in opposition to the fingers, so that a grasp may be made between them, forming of the human hand the perfect instrument that it is. 
In the monkey and other animals endowed with clavicles, the thumb moves like an ordinary finger, and the two fore-extremities must be opposed to each other 
to enable them to perform perfectly the act of prehension. — J. P. 



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43 

peculiarities and natural affinities. But we could never have supposed that any such uniformity of plan ran through them all, 
unless we had examined their intimate structure and composition. Then it is that we readily see the analogies by which they 
are associated, and trace the unity of design which runs through the whole scheme. 

The muscles of the palm of the hand are necessarily numerous, owing to the variety of the movements which the hand 
and fingers are required to perform. Were we to arrange them according to their actions and uses, we should have a group 
consisting of flexors, another of adductors, a third of abductors ; it is, however, found much more convenient to arrange them 
according to the positions which they occupy. Viewed in this way, they admit of being divided into three sets, those of the 
thumb, of the little finger, and those which occupy the intervening space in the middle of the palm. The palmar muscles of the 
thumb form that fleshy mass which, in popular language, is called the ball of the thumb ; they are four in number, viz. the 
abductor, the opponens, the short flexor, and the adductor. The abductor is a flat thin muscle, fig. 2, No. 8 ; it is placed imme- 
diately under the skin, extended obliquely from the anterior annular ligament of the wrist and the scaphoid bone to the outer 
edge of the first phalanx of the thumb at its base ; it is broader at its origin than at its insertion, as it gradually narrows to a 
short tendon near the latter point. It is covered merely by the skin and a thin membrane, derived from the palmar fascia. 

The opponens muscle of the thumb, fig. 3, No. 7, is thicker than the preceding, under which it lies, so that in order to bring 
it into view, the abductor must be detached at its origin and reflected downwards, or the middle part may be removed and the 
attachments allowed to remain, as in the drawing before us, fig. 3, Nos. 4, 5. The opponens will then appear a small triangular 
muscle, extending from the outer part of the annular ligament and the surface of the trapezium bone to the metacarpal bone of 
the thumb, into the outer border of which its fibres are inserted along its entire length. It is aponeuretic at its extremities, and 
fleshy along its middle. 

The short flexor muscle, fig. 3, No. 6, arises from the lower border of the annular ligament, and from the reflected part of 
it which binds down the tendon of the flexor carpi radialis ; some of its fibres are also attached to the trapezium bone. The 
fibres of the muscle proceed outwards and forwards, gradually narrowing to a short tendon, which, after being attached to the 
external sesamoid bone, becomes fixed to the base of the first phalanx of the thumb. The contiguous fibres which arise from 
the os magnum, and are inserted into the internal sesamoid bone, are usually considered a part of the short flexor ; we here join 
them to the adductor. 

The adductor muscle of the thumb, fig. 4, No. 6, is broad and triangular in its form, representing a flat plane of fleshy 
fibres, placed deeply under cover of the. preceding muscles, a part only of the anterior fibres projecting before them, fig. 3, No. 9. 
It arises from the anterior border of the third metacarpal bone, from the os magnum and the trapezoid bone, also by a few fibres 
from the trapezium. The anterior fibres pass transversely outwards, those higher up become more and more oblique, so that 
they converge, and become narrow towards their insertion, which is effected by means of a narrow tendon, which, after being 
connected with the internal sesamoid bone, is fixed to the inner side of the first phalanx of the thumb ; the outer and upper 
part of the muscle is usually considered as forming a part of the flexor brevis. 

Actions. — On taking a general view of the muscles of the thumb, which are eight in number, we perceive that, though all 
of them are attached to the three bones, they come from three different situations, and necessarily differ much from one another 
in form and length, as well as in direction of their fibres. Three of them lie along the back part of the fore-arm and hand, 
Plate XIX. fig. 2, Nos. 6,7,8; one will be found at the front of the fore-arm, part of which is seen hi plate XX. fig. 3, No. 8 ; 
the remainder being the group of short muscles, which are shown here in Plate XX. figs. 2, 3, 4 ; the actions and powers of 
each of these muscles will readily be understood by considering their points of attachment, and the direction of their fibres. It 
should be recollected that there are three pieces of bone in the thumb, each of which is straightened or bent by appropriate 
muscles ; that all are joined together so as to admit of four separate movements, for they may be drawn backwards, forwards, 
inwards, outwards, which movements are technically called extension, flexion, adduction, abduction. Now there are three 
extensor muscles, one for each bone, viz. the extensor of the metacarpal bone, that of the first and the second phalanx. These 
are the muscles above referred to as being placed at the back of the limb ; their antagonists in action, the flexors, are also three 
in number, and lie at the palmar aspect of the hand. The opponens of the thumb may be considered a flexor of the metacarpal 
bone, the short flexor bends the first phalanx, and the long flexor the second. There remain the abductor and adductor, which 
are also opposed to one. another in situation as well as in action; one being superficial and external, fig. 2, No. 8; whilst the 

PLATE XXII. 

This drawing is intended to exhibit the external oblique muscle of the abdomen, and its different points of attachment; the skin and the 
fascia are removed, so as show its relations at its origin to the pectoral, serratus, and latissimus muscles. 

No. 1. The sternum. 2. Linea alba. 3. Umbilicus. 4. The symphysis of the pubes. 5. The crest of the ilium. 6, 6. The lowei 
part of the pectoral muscles. 7. Part of the latissimus dorsi. 8. Part of the great serratus muscle. 9. The external oblique muscle 
of the abdomen, (m. obliquus extemus abdominus.) 



44 

other is deep-seated and internal, fig. 4, No. 6. The former is evidently fitted to draw the thumb away from the other fingevs, 
in which it is powerfully assisted by the extensor of the metacarpal bone, which is frequently called from this circumstance the 
long abductor ; the latter, as its name implies, and as is obvious from the number and direction of its fibres, draws the thumb 
towards the other fingers. If these moving powers be made to act successively upon the osseous pieces under their control, they 
will make the thumb move round as if in a circle, or perform what is technically termed circumduction ; in which movement it 
describes a cone, whose summit is at the carpal articulation, whilst its base is represented by the line which its distal extremity 
traverses. 

The four tapering fleshy fasciculi which are seen in fig. 2 and fig. 3, attached to the deep-seated flexor tendons, are called 
lumbricales, from some resemblance in their form to an earth-worm; they may be considered as appendages to the tendons of 
the deep muscle just named. The first lumbricalis arises from the outer border of the tendon, which goes to the fore-finger ; the 
second from that of the middle finger ; the third from the contiguous margins of the tendons going to the middle and ring-fingers; 
and the fourth from the latter and that of the little finger. As they proceed forwards they become round and tapering, and each 
ends in a tendinous process, which is fixed to the outer edge of the extensor tendons, lying over the fingers with which they 
correspond ; they appear to assist in flexing the fingers by acting on their first joint. 

Muscles of the Little Finger. — The fleshy mass placed along the inner border of the hand consists of four muscles, three 
of which act on the little finger, the other being merely cutaneous. The cutaneous muscle is that by which we are enabled to 
constrict and pucker the skin upon the inner border of the palm of the hand. It consists of a flat and very thin plane of fleshy 
fibres, which run obliquely inwards, from the anterior surface of the annular ligament and of the palmar fascia, and become fixed 
into the skin, along the inner border of the palm of the hand, for about an inch in length ; it is usually called palmaris brevis, 
fig. 2, No. 5. The abductor muscle of the little finger, fig. 2, No. 6, lies along the inner edge of the hand ; it is long and some- 
what compressed, broader at its middle than at its extremities ; it arises from the pisiform bone and from the tendinous fibres, 
which connect it with the annular ligament: its muscular fibres as they proceed forwards gradually end in a narrow tendon, 
which becomes attached to the inner border of the base of the first bone of the little finger, where its fibres are connected with 
those of the flexor brevis. 

The short flexor of the little finger, fig. 2, No. 7, fig. 3, No. 12, varies much in form and size, and sometimes does not exist. 
It arises by short tendinous fibres from the annular ligament at its anterior border, and from the hook-shaped bone at the wrist, 
from whence it proceeds obliquely forwards to be inserted into the base of the first phalanx of the little finger. The opponens 
of the little finger, fig. 4, No. 2, is concealed by the preceding muscles, which must be removed in order to bring it into view ; it 
may be considered an adductor of the fifth metacarpal bone, as the opponens of the thumb is of the first, fig. 4, No. 5. It arises 
from the hook-shaped bone and from the annular ligament of the wrist, and is inserted into the inner border of the fifth meta- 
carpal bone, its fibres gradually spreading out as they proceed to their points of attachment. The names of these muscles 
sufficiently indicate their actions. 

The Interosseous Muscles. — These are divided into two groups, one of which is seen at the dorsal aspect of the hand, 
between the metacarpal bones; from which circumstance they are called the dorsal interossei. They are four in number, and 
are shown in Plate XIX. figs. 1, 2 ; also in Plate XX. fig. 1. We have already described them in pp. 39, 40. 

When the flexor tendons are removed, as in fig. 4, Plate XX. the deep-seated muscles of the palm of the hand are brought 
into view ; all the interossei are seen, for the dorsal group dip downwards and become perceptible in the palm. Nos. 7, 9, 10, 12, 
mark the dorsal group, whilst Nos. 8, 11, 13, indicate the palmar set. The first palmar interosseous muscle, No. S, is a thin, 
compressed, fleshy fasciculus, which rests upon the second metacarpal bone, at its inner side ; it ends in a narrow tendon, which 
is fixed into the expansion of the extensor tendon over the fore-finger, at the inner side of the base of its first phalanx. The 
second palmar interosseous muscle, No. 11, lies along the fourth metacarpal bone at its outer border; it is inserted into the outer 
border of the extensor tendon, covering the ring-finger. The third, No. 13, lies upon the outer side of the fifth metacarpal bone, 
and is inserted into the corresponding border of the extensor tendon. The tendons of these muscles are also connected with tin: 



PLATE XXIII. 

Fig. 1 . Shows the two planes of intercostal muscles. 

No. 1. The dorsal vertebrae. 2, 2. The heads of the ribs attached to them. 3, 3, 3. Ribs. 4. The external plane of intercostal muscle, 

the direction of its fibres being downwards and forwards. 5, 5. The internal plane of intercostal muscles, the fibres being directed 

downwards and backwards. 
Fig. 2. Shows the internal oblique muscle, the direction of its fibres, and its different points of attachment. 
No. 1. The lower ribs. 2. The crest of the ilium. 3. The umbilicus. 4. The linea alba. 5. The fleshy fibres of the internal oblique 

muscle (m. obliquus ascendens abdominis.) 6. Its aponeurosis, extending forwards to reach the linea alba. 7. Part of the latissunus 

dorsi muscle. 



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45 

first phalanges of the fingers to which they belong. From the direction of the fibres of these fleshy fasciculi, it is obvious that 
they are enabled, to incline the fingers to which they belong inwards or outwards, and, by a simultaneous movement, to separate 
them one from each other, or spread them out, and then draw them together again. 



PLATE XXI. 

The two broad muscles of the back are here seen in their entire extent, Nos. 10 and U ; the other references belong to 
muscles which we have previously noticed, or which will be given in subsequent drawings. The muscles of the back are 
generally considered as being arranged in layers just as we find them in prosecuting their dissection. The two which we here 
mark off form the first layer, for they lie immediately under the skin, one extending from the occiput to the lower part of the 
back, the other from the middle of the back downwards to the pelvis and lower part of the spine. The trapezius muscle, fig. 10, 
extends along the posterior part of the neck as well as of the back and shoulder. If the muscle of one side be taken by itself, 
its form is triangular ; but both together represent a quadrilateral figure, whose four sides are not equal, and none of its sides 
parallel, from which circumstance its name is taken. The fibres of the trapezius muscle are attached to the external protuberance 
of the occipital bone, and for a short way to the oblique ridge leading outwards from it. Plate XXI. No. 1. In the neck the 
fibres of both muscles are united in the middle line, and are also connected with a tendinous band, which is attached to the spinous 
processes of the vertebra ; lower down they take origin from the spinous process of the last cervical vertebra, and from all those 
of the dorsal region, as well as from the ligaments which connect them. From these different points the fibres proceed towards 
the spine of the scapula, the top of the shoulder, and the external part of the clavicle, into which they become inserted. The 
fibres which come from the last cervical and the upper dorsal vertebra pass horizontally outwards ; those above them descend, 
while those below them ascend. The line of insertion into the upper border of the spine of the scapula and of the acromion 
process are marked 4 and 3. This muscle is fleshy in the greater part of its extent, but its points of attachment are tendinous. 

The broad muscle of the back, latissimus dorsi, No. 11, is of very considerable extent, as its name implies. It extends from 
the lower half of the spine and from the back part of the pelvis obliquely outwards over the loins and the side, and across the 
axilla to the arm. Its lower and back part consists of a broad aponeurosis ; the rest forms a flat plane of muscular fibres, which 
gradually become aggregated together so as to form a thick narrow fasciculus as it proceeds towards its insertion. Its commencing 
fibres are attached to the spinous processes of the six lower dorsal vertebrae, where they are covered by the trapezius ; lower 
down they are attached to the spinous processes of the lumbar region and the sacrum, and to the supra-spinous ligaments ; they 
are also seen to be attached to the crest of the ilium, No. 6. The broad aponeurosis which thus commences gives origin to the 
fleshy fibres which form the rest of the muscle ; some of these, however, have a separate origin, for at its lower and outer border 
three or four points are seen, which, starting from the lower ribs, proceed obliquely upwards and forwards, and become blended 
with the rest of the muscle. The upper border of the latissimus muscle slides over the inferior angle of the scapula and the origin 
of the teres major, (15) ; the narrow fasciculus into which its fibres are collected forms the posterior fold of the axilla, where it 
turns upon the teres major so as to get in front of it, and then ends in a flat tendon about an inch and a half in breadth, which is 
inserted into the posterior border of the bicipital groove in the humerus. 

Actions. — The trapezius muscle can be made to act on the head, on the shoulder, or on the spine. Thus, if the shoulders be 
fixed, the upper fibres are enabled to draw the head either backwards or to their own side ; if the spine and head be fixed, the 
shoulder can be drawn backwards, particularly if another muscle, (the rhomboid,) which lies under it, and part of which is here 
seen, No. 18, be made to act at the same time. It raises the shoulder; but the scapula seldom moves directly backwards, or up- 
wards, or downwards ; these changes in its position are generally found accompanied by a movement of rotation, by which it i 
made to turn as if on a pivot driven through its centre. 

When the latissimus muscle acts on the shaft of the humerus, it can obviously draw it downwards and bring the limb closely 
lo the side • but at the same time it gives it a rotatory motion on its axis. If the shoulder and arm be fixed, the latissimus muscle 
can be made to assist in inspiration, by elevating the lower ribs ; it also assists in drawing up the body in the effort of climbing. 
On the same principle this muscle and the pectoralis major enable a person to avail himself of the assistance of crutches ; the 
top of the crutch serves as a fulcrum which supports the arm, and as the margins of these muscles rest upon it, they are enabled 
to draw the body upwards towards it as to a fixed point. When the shoulder and" arm are fixed, the trapezius anil latissimus 
muscles are enabled to act upon the spine, particularly in restoring the body to the erect positiop when it inclines (o either side. 
On lookino- at the plate, it will be at once perceived that the fibres of the trapezius may be made to act from the shoulder upon 
the spine in a considerable part of its length, provided the shoulder is rendered fixed. The latissimus muscle can act in the same 
way upon the lower half of the spine if the arm be placed in the same position as is here represented, viz. thrown out from the 
side and steadily fixed by the action of its muscles; this preparatory movement would enable both muscles together to act upon 



46 

ili«. spine. Suppose an individual when walking upon a narrow board finds himself inclining to the left side so much as (o be in 
danger of losing his balance, he instinctively throws out his right arm in order to give these two muscles fixed points at their 
outer ends, which at once enables them to draw upon the spine and restore it to the erect posture. In the position here supposed, 
the spine for the moment forms a curve, whose concavity is to the left side, and convexity to the right, by which means the upper 
part of the trapezius and the lower part of the latissimus of the right are put into a state of tension, inasmuch as their points of 
attachment are farther separated than when in the condition of repose, whilst the middle fibres are somewhat relaxed ; under 
such circumstances the fibres of the muscles which are attached to the upper and lower ends of the spine will be made by an 
effort of the will to pull upon them, and draw them to their own side : at the same moment those portions of the corresponding 
muscles of the opposite sides which are attached to the middle part of the spine, (which in the case here supposed are rendered 
tonse,) are enabled not only to fix that part of the column so as to enable the muscles of the opposite side to act more steadily 
upon its extreme points, but by a continuance of their effort they can even draw that part towards their own side ; by this com- 
bination of efforts it is that the spine, like a flexible column, is subjected to the influence of forces which act upon it from opposite 
Bides, and restored to its equilibrium by a nice adjustment of power directed by a voluntary and instinctive impulse. To maintain 
himself erect the rope-dancer uses a pole, which he holds with both hands in the horizontal position, and which he inclines now 
to one side, now to the other; the pole is his only security, for by grasping it firmly he can render his arms fixed, and thereby 
give to the muscles points from which ttiey may act upon the spine, so as to straighten the curves or lateral flexures into which 
it is necessarily thrown during his various evolutions. 



PLATE XXII. 

A side view of the body is here given in order to show the first stratum of muscular fibres which covers the abdomen. Its 
points of attachment to the ribs are disposed in a peculiar way with regard to the great pectoral muscle, the serratus, and the 
Latissimus, which are here indicated ; its insertion into the haunch-bone is also obvious, moreover, in the interval between the 
lower margin of the chest and the most projecting part of the haunch-bone ; the muscular fibres end in a broad flat membrane 
or aponeurosis, which is prolonged inwards over the fore part of the abdomen, so as to become blended with a similar production 
from the muscle of the opposite side along the whole space from the lower extremity of the breast-bone to the pubes. The line 
of junction here indicated is termed the white line, (linea alba, No. 2) ; it is distinctly shown in plate XXIV. No. 14, in which 
the aponeuroses are cut away at each side, and a mere narrow cord left, which is formed by the junction of their fibres ; it may be 
considered as the common point of junction of the three pairs of muscles which form the parietes of the abdomen ; it is interposed 
between the two recti muscles, which in plate XXII. are seen somewhat to project in slight relief from under the aponeurosis 
which covers them; but in plate XXIV. the rectus of the left side is seen distinctly in its entire length, the aponeurosis being 
removed in order to expose it. The white line (linea alba) is broader at its upper than at its lower extremity, for there a wider 
interval exists between the recti muscles. At its middle the umbilicus or navel exists, which may be considered a cicatrix remain- 
ing after the closure of the aperture which gives passage to the umbilical cord during foetal life. 

The muscles which cover the abdomen, and form the walls of that cavity from the ribs and sternum to the pelvis, at the 
front, at the sides, and backwards even to the lumbar part of the spine, are three broad flat planes composed of fleshy and 



PLATE XXIV. 

This drawing represents the transversalis muscle of the abdomen, the external oblique muscle and the internal oblique having been removed 
in order to show it more fully ; the greater part of the rectus muscle of the right side is also taken away with the same view, and also 
to show that at the lower part of the last named muscle the aponeurosis of the transversalis muscle passes in front of it, though higher 
up it passes behind it. 

No. 1. The sternum. 2. The cartilages of the ribs. 3. The crest of the ilium. 4. The pointed processes by which the great serratus 
muscle arises. 5. A part of the external oblique muscle of the abdomen left upon the ribs, where its fibres will be seen insinuating 
themselves between those of the serratus. 6. Part of the latissimus dorsi muscle, its anterior edge being everted in order to expose 
the aponeurosis, which passes backwards from the transversalis muscle deeply into the lumbar region, where it becomes attached to the 
roots and points of the transverse processes of the vertebrae, after having formed a sheath for the quadratus muscle. 7. The transversalis 
muscle of the abdomen, (m. transversus abdominis, m. lombo-abdominal.) 8. Its aponeurosis, where it lies behind the rectus muscle. 
9. The lower part of its aponeurosis, where it passes in front of the muscle. 10. A transverse section of the rectus muscle of the right 
side, the upper two-thirds of it being removed. 11. The rectus muscle of the left side. I2-The lower part of the transversalis muscle, 
where it passes over the spermatic cord. 13. The umbilicus, or navel. 14, 14. The linea alba. 



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47 

tendinous fibres, placed one over the other, the fibres of each running in a different direction from the others ; from which 
circumstance, the external one, seen in plate XXII., is called the oblique muscle, with descending fibres : the next, 'seen in plate 
XXIII., is the oblique muscle, with ascending fibres : and the third, plate XXIV., No. 7, is the transverse muscle. In front there 
is a pair which extends from the lower part of the chest directly down to the pubes, and is thence called the recti muscles, plate 
XXIV. No. 11. We frequently find an accessory pair in the form of two small triangular muscles that rest upon the lower part 
of the recti, extending from the pubes about two inches, or two and a half inches upwards. 

The external oblique muscle, as seen in plate XXIII. No. 9, is called also the descending oblique muscle, from the direction 
of its fibres ; it is situated at the side and front of the abdomen, and represents a broad flat plane of muscular and aponeurotic 
fibres. It is very broad at its anterior margin, for it extends from the ensiform cartilage to the pubes ; the posterior border is 
very narrow, oblique in its direction, and composed of fleshy fibres, extended from the last rib down to the ilium ; the upper 
border is irregularly curved, and composed of seven or eight angular points, termed digitations, which are interposed between 
similar processes of the serratus magnus and the latissimus dorsi. The first or highest of these digitations is very thin, but still 
is prolonged, so that its border becomes blended with the lower edge of the great pectoral muscle, whilst its extremity is fixed to 
the fifth or sixth rib, beneath the corresponding point of the great serratus muscle ; the second, third, and sometimes the fourth 
fleshy points are broader than the first, whilst the three last are very narrow and pointed. The digitations in each case are 
observed to commence with very short white tendinous fibres, to which the fleshy fibres soon succeed, and are thence prolonged 
obliquely downwards and forwards ; those of the five upper digitations run into the broad aponeurosis, by which they are con- 
tinued onwards into the linea alba, whilst those of the three last are inserted into the anterior half of the haunch-bone, (os ilii). 
The lower border of the muscle presents two parts : one fleshy, with a slight admixture of tendinous fibres, which are here seen 
inserted into the ilium ; and the other tendinous, where the broad aponeurosis is stretched across from the prominent process 
(spinous) of the ilium to the pubes. This border, when detached from all its connexions, represents a flat tense band or cord, 
attached on the outside to the spine of the ilium, and on the inside to the spine of the pubes ; by which arrangement provision 
is made for the passage of muscles, blood-vessels, and nerves downwards, from the abdomen into the thigh, through the space 
which intervenes between the under edge of the cord and the curved margin of the pelvic bones. From this circumstance the 
space is termed the crural arch ; the lower fibres of the aponeurosis will be observed, moreover, to separate from one another so 
as to leave between them an angular interval, which transmits the spermatic cord in the male, or the round ligament in the female. 
It is, in fact, the outlet of a canal formed by a very peculiar arrangement of the lower part of these three muscles, the inlet or 
inner aperture being in a thin membrane, which lines the inner surface of the transversalis muscle, and is distant from the one 
here delineated by about one inch and a half. Provision is thus made for the security of the abdominal viscera, and for the pre- 
vention of their protrusion, inasmuch as the two apertures just noticed are not directly opposed to one another, which would 
render the egress of parts comparatively easy. The arrangement here indicated gives to the canal such a degree of obliquity in 
its course as to enable it to act on the principle of a valve in preventing protrusions. The outer aperture through which the cord 
passes will be observed to be somewhat of an angular form, being bounded by the diverging fibres of the aponeurosis of the 
external oblique muscle as they proceed to their insertion. Upon the aponeurosis some fibres will be observed to rest, but which 
run in a different direction, viz. upwards and inwards. They are well marked towards the outer angle of the aperture, and as 
they are interwoven with the subjacent fibres, they have the effect not merely of strengthening them in a part which requires 
some additional security, but also preventing the enlargement of the aperture. These transverse fibres, moreover, are continued 
downwards upon the cord as it escapes from the opening, but there they gradually become thin, so as to represent a smooth 
membrane, which shades off the margins of the aperture so as to render them indistinct until it is removed by dissection. Where 
this structure is continued downwards, it assumes a membranous form, and becomes one of the coverings of the cord. 

Now there is much of technical language employed in the description of the parts here noticed. The tense cord, which 
represents the lower margin of the external oblique muscle, is called PouparVs ligament; the aperture is called the ring, 
(external abdominal,) notwithstanding its angular form ; the fibres which form its sides are called pillars, (columns; ;) the trans- 



PLATE XXV. 

This drawing gives a posterior view of the sternum and ribs, which form a covering for the chest, and of the transversalis and recti muscles, 
as they lie over the abdomen; the clavicles and ribs are cut through towards their anterior third, the incision is then continued down- 
wards through the three planes of abdominal muscles, and through the iliac bones; the anterior third of the walls of the trunk arc thus 
detached and everted, in order to show at one view their under or posterior surface. 

Nos. 1,1. The clavicles. 2. The sternum. 3. The ensiform cartilage. 4. The pubic bones at their symphysis. 5, 5. The iliac bones. 
6, 6. The triangular muscle of the sternum, (m. triangularis sterol.) 7. The deep or under surface of the rectos muscle of the abdo- 
men, which is here brought into view by the removal of the back part of the sheath, which the internal oblique and transversalis 
muscles form for it. 8. The lower part of the rectus muscle of the left side, where it is left uncovered by the aponeuroses of the 
muscles. 9. The transversalis muscle of the right side. 10. The transversalis muscle of the left side. 11. Its aponeurosis. 



48 

wise curved fibres which run across are called intercolumnar fibres ; and finally, whero the latter are prolonged down upon the 
cord, and assume the form of a thin membrane, they are said to form the fascia of the cord, or the spermatic fascia. 



PLATE XXIII. 

Fig. 1. This drawing is intended to show the structure and the arrangement of the fibres of the intercostal muscles which 
fill up the spaces between the ribs, and assist materially in the respiratory movements. In each space there are two planes of 
fleshy and aponeurotic fibres, which differ in their direction, and also in the extent to which they are prolonged. The external 
intercostal muscle, or rather plane, of muscular fibres, No. 4, will be observed to have a direction downwards and forwards, from 
the lower margin of any given rib to the contiguous edge of that beneath it. Its extent is from opposite the transverse processes 
of the dorsal vertebrae to near the anterior extremities of the ribs, at which point the muscular fibres cease, and a thin layer of 
membrane is continued onwards to the sternum. 

The internal intercostal muscle, placed under cover of or beneath the former, takes an opposite direction, the fibres runnin» 
backwards and downwards, 5, 5 ; they may be said to commence at the sternum, to be attached by their extremities to the car- 
tilages of the ribs, between which they lie, and to be then continued backwards between the bodies of the ribs themselves as far 
as their angles. Between the two planes of muscles here noticed, the intercostal nerves and vessels are placed. Their actions 
we shall notice when we comment on those of the Diaphragm. 

Fig. 2. The second muscular layer which enters into the composition of the walls of the abdomen is here shown. 

Fig. 2, No. 5. From its position, and from the direction of its fibres, this muscle is called the " internal oblique," and as 
most of its fibres incline upwards, it is not unfrequently called " obliquus ascendens." It is flat, broad, and thin, composed of 
fleshy fibres in a considerable part of its extent, but towards the fore part it becomes aponeurotic, No. 6 ; its fibres are attached 
along the crest of the ilium for two-thirds of its extent, and also to the outer two thirds of Poupart's ligament ; this extent repre- 
sents the lower border, or, as it is commonly termed, the origin of the muscle. Along its upper edge it will be seen to be fixed 
to the cartilage of the ribs, from the twelfth to the seventh, inclusive. The muscular fibres will be observed to pass into a broad 
aponeurosis, which at the outer border of the rectus muscle divides into two layers, of which one passes before and the other 
behind the flat muscle just named, so as to enclose it in a sheath. At its inner border they unite again, and become blended 
with the fibres of the corresponding muscle of the opposite side, from the ensiform cartilage to the pubic bone. Noav the layer 
of aponeurosis which passes in front of the rectus muscle becomes identified with that of the external oblique muscle as in Plate 
XXII., and that which passes behind the rectus unites with the aponeurosis of the transversalis muscle, as in Plate XXIV. The 
arrangement here indicated exists as far as from the ensiform cartilage to midway between the umbilicus and the pubic bone 

PLATE XXVI. 

The structure of the diaphragm, and its different points of attachment, are here exhibited as they are seen from the cavity of the abdomen 

after its soft parietes have been cut through and removed, together with the whole of its contained viscera. 
No, 1. The sternum. 2. The ensiform cartilage. 3, 3. The ends of the true ribs. 4,4. The cartilages of the false ribs. 5 G 7 8 9. 
The crest of the ilium. 10, 11, 12. The cut edges of the three layers of abdominal muscles of the right side, divided by'an incisbri 
carried downwards from the ribs to the ilium. 13. The aponeurosis of the transversalis muscle, where it is prolonged inwards, and 
ia about to form a sheath for the quadratus lumbonim muscle. 14. The quadratus lumborum muscle of the left side, brouo-ht into view 
by the removal of the aponeurosis of the transversalis. 15. The great psoas muscle; it is seen to rest against the side of the lumbar 
vertebra; and to cross the brim of the pelvis, as it descends towards its insertion into the small trochanter of the thighbone; its upper 
end is crossed by the arched ligament (25) of the diaphragm (ligamentum arcuatum;) it then overlaps the quadratus muscle whilst in 
the lumbar region, and the inner edge of the iliacus whilst crossing the pelvis; lower down it becomes inseparably united with the 
latter previous to its insertion. 16, 16. The iliac muscles, so named from resting upon the hollow of the iliac bones 1 7 The right 
division, or leaflet of the tendon of the diaphragm. 18, 19. The middle and the left divisions of the same. 20, 20 The muscular 
fibres of the diaphragm, where their direction is horizontal. 21. The anterior fibres of the same, their direction being backwards from 
the ensiform cartilage. 22, 22. The lateral part of the muscle, where the fibres are oblique. 23, 23. The deep or posterior part, the 
fibres of which pass forwards. 24, 24, The external arched ligament of the diaphragm; it is continuous with the anterior layer of 
the aponeurosis of the transversalis muscle, and gives attachment to the fibres last named of the diaphragm. 25, 25. The inner or 
proper arched hgament of the diaphragm, (ligamentum arcuatum proprium.) 26. The right crus or pillar of the diaphragm, com- 
mencing by a tendinous process from the lumbar vertebra. 27. The left, or smaller crus. 28. The fleshy part of the left crus. 29. 
The fleshy part of the right crus. 30. The aorta passing down through the interval between the crura. 31. The (Esophageal opening 
in the diaphragm. 32. The opening for the vena cava. ° 



Muscles 



Plate Z6 













49 

at which point both layers of the internal oblique, and also that of the transversalis muscle, pass in front of the rectus, Plate 
XXIV., Nos. 9, 10, also Plate XXV., No 8, where the lower part of the rectus is left to show that the aponeuroses do not exist 
at its posterior or abdominal surface. The fibres of the internal oblique muscle which arise from Poupart's ligament become 
gradually thin and pale ; they assume a direction downwards and inwards, arching over the spermatic cord, and become fixed 
to the crest of the pubic bone, and into that ridge upon it which is called the pectineal line. The latter part of the muscle 
becomes united with the subjacent fibres of the transversalis and assume the name of conjoined fibres or tendons of these 
muscles. The posterior border of the muscle is narrow, as it corresponds with the interval between the crest of the ilium and 
the last rib ; at this point the fleshy fibres become attached to the aponeurosis of the latissimus dorsi muscle, which will be 
observed everted, in order to show the fascia here alluded to. At the lower part of the drawing a flat piece of white membrane 
will be observed turned out of its place and thrown down upon the thigh; it is a part of the aponeurosis of the external oblique 
muscle everted, in order to bring into view the relation which the lower border of the subjacent muscle bears to the cord. 

The cremaster muscle rests upon the spermatic cord, and supports the testis, (s^ao, to suspend). It consists of a number 
of thin fibres disposed in curved lines, the concavities all looking upwards. They are indicated in Plates XXII. and XXIII.; 
they are on the same plane as the lower border of the internal oblique muscles and appear to have been originally continuous 
with it ; their extremities have the same points of attachment, viz. to Poupart's ligament and the crest of the pubic bone, and 
they do not exist before the testis has descended. For these several reasons it may be considered a part of the internal oblique 
muscle drawn down with the testis, the direction of the fibres being determined by the traction exerted upon them during the 
descent of the organ just named. 



PLATE XXIV. 

The third muscular layer of the abdomen is here exhibited, viz. the transversalis muscle, No. 7, with its aponeurosis, No. 8, 
and the relation of that aponeurosis to the rectus muscle, both in the upper two thirds of its extent and in the lower third. The 
transversalis muscle, like the two oblique muscles previously noticed, consists of a broad thin plane of muscular and tendinous 
fibres. At first view its form appears to be triangular, one side being represented by the linea alba (14, 14,) extending from the 
ensiform cartilage to the pubic bone ; another side, by the cartilages of the ribs, No. 2 ; and the third by the crest of the ilium, 
No. 3, and by Poupart's ligament. However, when we examine the muscle farther back, in the interval between the last rib 
and the ilium, it does not terminate in a point ; its fleshy fibres become continuous with a membrane which is prolonged back- 
wards, and becomes attached to the lumbar vertebrse in a very peculiar way, after having formed a sheath for the quadratus 
lumborum muscle. The fleshy fibres of the muscle may be said to arise above from the cartilages of the ribs, from the seventh 
to the twelfth, by their inner edges ; below, from the inner edge of the crest of the ilium in three-fourths of its extent, and from 
the outer half of Poupart's ligament ; and finally, in the interval between the last rib and the ilium, from the fascia just alluded 
to, and which shall be more particularly described when commenting on Plate XXVIII. The fleshy fibres proceed inwards and 
end in a broad aponeurosis, which soon becomes identified with the aponeurosis of the internal oblique muscle, with which it is 
prolonged to the linea alba, where it becomes blended with the fibres of the corresponding muscle of the opposite side, as well as 
with those of the oblique muscles, forming with them a seam, or common line of junction. The whole of the aponeurosis of the 
transversalis muscle lies behind the rectus muscle, in the upper two-thirds of its extent, No. 8, but passes in front of it in the 
lower third, No. 9 ; this relation is also indicated in Plate XXV. The lower border of the muscle, No. 12, where it arises from 
Poupart's ligament, becomes rather thin and weak ; its fibres incline inwards over the spermatic cord, previously to their inser- 
tion into the crest and pectineal line of the pubic bone. 

The rectus or straight muscle of the abdomen is here shown, extending from the lower margin of the chest to the crest of 
the pubic bone, gradually becoming narrow towards its lower attachment ; see also Plate XXV., No. 7. Its upper attachment is 
effected by three points, of which one, the smallest, is fixed to the ensiform cartilage and the cartilage of the seventh rib ; the 
second, to the cartilage of the sixth rib ; and the third, to that of the fifth. The fibres, when traced downwards, will be found 
interrupted by two, three, or sometimes four zigzag tendinous lines (linea? transversa;), which run across it, one of them being 
opposite the ensiform cartilage, one at the umbilicus, and the third in the interval between these ; they are more distinct upon the 
anterior than the posterior surface. When traced downwards, the fibres of the muscle will be found to end in a flit tendon, 
which is inserted by two points into the upper edge of the pubic bone. The rectus muscle is enclosed in a sheath formed by the 
aponeurosis of the internal oblique muscle, which divides into two layers, so as to enclose it; the external layer being identified 
with and strengthened by the aponeurosis of the external oblique muscle, and the internal by that of the transversalis ; but the 
sheath will be found deficient at its back part, towards the lower fourth or fifth of its extent, No. 8. Where the af>oneui 
divides to enclose the rectus, it presents necessarily a curved line, corresponding with the outer border of the muscle, which is 
usually named linea semi-lunaris. 
' Muscles. — 7 



50 

The pyramidal muscle (m. pyramidalis) is a small flat muscular bundle of a triangular form ; when it exists, which is not 
always (he case, it rests upon the lower extremity of the rectus muscle, is attached below to the pubic bono, near its symphysis, 
and above to the linea alba. Its surfaces are flat, the lower edge is tendinous and straight, the outer is oblique, the inner is also 
straight, the fibres being vertical, and parallel with the linea alba, close to which it lies, its power is necessarily very restricted; 
it may render the linea alba tense by drawing upon it. 

Actions.— The three planes of muscular fibres here described are so arranged in the greater part of their extent as mutually 
to support and give strength to one another. The direction of the fibres of the internal oblique crosses that of the external, and 
that of the transversalis differs from both; hence, wherever this arrangement takes place, intestinal protrusions are prevented by 
the mode in which the fibres are super-imposed one upon the other. But towards the lower part of the abdomen, the fibres of 
all take nearly the same direction, being inclined downwards and inwards; there also, those of the internal oblique and trans- 
versalis become thin, and an interstice is moreover left beneath their lower margin for the transmission of the spermatic cord. 
Hence it is in this latter position that the intestines usually protrude, constituting hernia, or rupture. It would be limiting the use 
of these structures to say they serve merely to enclose and support the abdominal viscera. Their contracting power enables them 
to assist in many important functions, as well as in actions of the body: and as their position and points of attachment establish 
relations between them and the chest, the pelvis, and the cavity of the abdomen, we see how they can act upon either. Suppose 
their points of attachment to the chest and pelvis be rendered fixed by a preparatory effort of other moving powers, determined 
by the will, these muscles will be at once enabled to act upon the cavity of the abdomen, to diminish its capacity, and thereby 
the viscera it contains, particularly if an effort of inspiration be at the same time made, so that the diaphragm, as it descends, 
may force down the organs with which it is in contact. The combination of such movements as these is necessary in vomiting, 
and other expulsive efforts. The same agents, particularly the internal oblique and transversalis, can occasionally be made to 
compress the lower border of the chest, and thereby assist in expiration. When the lower attachment of these muscles becomes 
fixed, so as to give them a steady point from which to act, they can be made to move the trunk in various ways. Thus the two 
recti, by drawing on the lower part of the chest, can bend the body directly forwards, and so become flexors of the trunk. It 
will at once be perceived that the ribs into which they are fixed give them a great mechanical advantage in executing this office; 
for, as these bones project forwards from the spine, they resemble so many prolonged transverse processes, and in effect give to 
the muscles the mechanical advantage of levers, through the medium of which they can act upon the vertebral column. The two 
external oblique muscles can assist the recti in thus bending the body directly forwards, when both act together; but if either 
contracts by itself, it in the first instance tends to draw down the chest towards its own side, but a continuance of the effort enables 
it to turn the body upon its axis, and rotate it towards the opposite side ; thus the right external oblique muscle rotates the body 
towards the left side, the centre of motion being in the lumbar vertebrae. If the chest be fixed, the oblique and recti muscles are 
enabled to concentrate their efforts upon the pelvis ; this is exemplified in the ordinary effort of climbing, in which the arms are 
raised above the head and rendered fixed by seizing on some object ; the ribs and chest are in the next place rendered motionless 
by taking a full inspiration, and by holding in the breath ; then it is that the abdominal muscles can act upon the pelvis, and draw 
it upwards and forwards, thereby preparing for an upward movement of the legs. Though the moving powers here described 
are grouped together as belonging to the walls of the abdomen, sufficient has been said to show how important an influence they 
exert upon the thorax. The external oblique rests upon the same plane as the great serratus muscle, whilst the internal oblique 
and transversalis occupy the same relative position in the abdominal region which the intercostals do in the thoracic. 



PLATE XXVI. 

This drawing is intended to exhibit the structure of the muscular partition, which in man and the higher animals separates 
the cavity of the chest from that of the abdomen ; technically it is called the diaphragm, (Su^aaou, to divide,) and in popular lan- 
guage it is known as the midriff. To bring it fully into view, all the viscera of the abdominal cavity must be removed, and the 
coating which the lining membrane or peritoneum gives to this, as well as to other parts, must be carefully dissected off. The 
vessels, too, which pass through it, as well as the oesophagus, are also cut across, in order that the form and position of the 
apertures which transmit them may be more distinctly seen. The great blood-vessels which lie upon the spine must also be 
taken away, in order to give a distinct view of the pointed processes, (footstalks, " legs," or " crura," as they are technically 
called,) by which the diaphragm is attached to the lumbar vertebra?. It is difficult to convey a correct or satisfactory impression 
of this structure by a single drawing, for its under surface, which is the one here seen, is concave, the upper surface being neces- 
sarily convex ; moreover, the degrees of its curvature differ at the right and at the left sides, and they vary every moment of our 
lives, for, like a moveable floor, it descends with every inspiration which we make, and ascends with every expiration. This can 
be rendered clear only by a series of outline drawings, giving side views of sections cf the body, which show at the same time 



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51 

the diaphragm in its different degrees of curvature, whilst it is descending in its contraction, and ascending in its relaxation ; the 
import of these remarks will be more clearly perceived by reference to the different sketches given in Plate XXVII. 

When placing the parts as prepared by dissection, in order to take this drawing, the lower ribs were drawn a little upwards, 
and also spread out somewhat at the sides, in order to make the fibres of the diaphragm tense. This gives the ribs necessarily 
somewhat of a formal appearance ; the ensiform cartilage (No. 2) is also drawn up hi order to show the fibres which are attached 
to it. Now, when viewed in this way from below, we perceive at once how the diaphragm is attached all round the lower rim 
of the chest, its fleshy fibres being fixed to the inside of the cartilages of the ribs from the seventh or last true rib, down to the 
last, (No. 24,) at each side ; a small bundle is also attached to the ensiform cartilage. Two tapering processes, (crura, or legs,) 
one of which is larger and longer than the other, rest on the spine, and are fixed to it ; finally, at each side of the spine, where, 
from the interposition of the psoas muscle, its fibres cannot be directly connected with any osseous structure, they arc attached to 
a curved ligament, (No. 25,) which arches outwards from the spine to the transverse process of the first lumbar vertebra. The 
structure of the diaphragm is partly muscular and partly aponeurotic, or tendinous ; the fleshy fibres which form the broad part, 
and which commence at the margin of the chest, are seen to terminate in white glistening fibres, which are interwoven so as to 
form a firm resisting membrane. The direction of the muscular fibrillar necessarily varies, so does their length ; those from the 
sides run transversely inwards, those from before are very short, and pass backwards, whilst the posterior sets ascend and come 
forward. The white or tendinous part, known as the " cordiform tendon," presents a right and a left branch, as well as a middle 
one, which are sometimes spoken of as leaflets, the whole being supposed to bear some resemblance to a trefoil leaf; the middle 
one, however, is here fore-shortened so much, and the shadow is thrown upon it in such a way, that it appears necessarily smaller 
and shorter than it really is. At the junction of the middle with the right division of the tendon a large square opening is observed, 
(No. 32,) which transmits the great vein, (vena cava,) that returns the blood from the lower parts of the body. Farther to the 
left and a little lower down is another opening, (31,) which gives passage to the oesophagus, or gullet, with the two great stom- 
achic nerves, (par vagum, — pneumogastric) ; it resembles a fissure, the long diameter of which is from above downwards ; it is, 
however, elliptical in its form and fleshy in its structure, its margins being formed by the muscular fibres of the crura as they 
ascend to be fixed into the central tendon. Still farther back and towards the central line is another opening, which resembles a 
canal or a tunnel placed between the crura, (28, 29) ; it gives passage to the great artery (30) (the aorta,) to a large vein, (azygos,) 
and to the principal trunk of the absorbing system, (thoracic duct.) 

The lower surface of the diaphragm is in apposition with the liver, the spleen, the upper extremity of the stomach, and 
farther back it supports part of the kidneys and their capsules. Its prolonged part (crura) is also in relation with the great vessels 
— aorta and vena cava, with the pancreas and the duodenum. The upper surface is in apposition at each side with the lungs, 
and between these with the heart and the pericardium. 

Actions. — The position and the structure of the diaphragm would lead us at first sight to class it amongst the involuntary 
muscles ; so also would the circumstance of its continuing to act when all volition is suspended during sleep or suppressed by an 
apoplectic seizure. Yet we are conscious of possessing a certain degree of control over its motions, for we can increase or 
diminish the extent of its movements, or hold it for a while at any particular state to which we have brought it by a previous 
effort. Seeing, then, that the muscle is thus allied to the two great classes of the voluntary and the involuntary, at the same time 
that it differs from each in some important particulars, we must associate it with those which form a group apart, and which are 



PLATE XXVII. 

The outline figures here given are intended to show the different states of the diaphragm, and the influence which its changes exert upon 
the size of the cavities of the chest and abdomen, also the manner in which it can assist in compressing the abdominal viscera. 

Fig. 1. The diaphragm is seen in the relaxed state in which it projects up into the thorax, thereby lessening its perpendicular depth, and 
diminishing' its capacity during expiration. The abdomen is at the same time proportionally increased. 

Fig. 2. When the diaphragm descends during inspiration, and increases the depth and the capacity of the chest, its curvature is lessened, 
for it approaches somewhat the state of an inclined plane. In its descent it also inclines forwards, which necessarily causes a certain 
degree of fullness at the umbilicus, towards which the abdominal viscera are pushed before it. This the drawing indicates. 

Fig. 3. The curve of the upper surface of the diaphragm is sketched so as to show the difference in its degree at the right and left side. 
Also that it represents at once the floor of the chest and the roof of the abdomen. 

Fig. 4. The manner in which the diaphragm and the abdominal muscles conspire to lessen the capacity of the abdomen is here shown. 
The oblique and transverse muscles, like broad belts, narrow its circumference, whilst the diaphragm presses downwards. When an 
effort is made to expel the contents of the intestinal canal, the body is inclined forwards, so that its axis may be made to coincide with 
that of the lower aperture of the pelvis. The fact is here expressed. 

Fig. 5. This sketch shows how the diaphragm at times forces down the viscera towards the inguinal region, and may be the in 

causing a hernia at one side or the other, according to the inclination which it is made to assume in different efforts. When, in lifting 
a heavy weight, a person inclines much towards the right side, as is here indicated, the viscera, particularly the small nit- stines, are 
pushed down towards the left groin, and if the resistance be not adequate, a protrusion is liable to occur. 



52 

termed mixed muscles. The changes of position which the diaphragm undergoes, as it passes alternately from a state of relaxa 
tion to contraction, materially influence the relative size of the two great compartments of the body between which it is placed. 
In fig. 1, Plate XXVII., the highest part of the curvature which its upper surface presents is on a level with the fourth intercostal 
space ; it is then relaxed, which is the state corresponding with expiration, the cavity of the thorax being at the same time 
necessarily diminished in every direction by the subsidence of the ribs and sternum, which takes place concurrently with the 
ascent of the diaphragm. But when we commence the effort of inspiration, the muscular fibres of the diaphragm contract and 
shorten themselves, so as to bring it down from the curved and arched state which it exhibits in fig. 1, to nearly that of an inclined 
plane as seen in fig. 2. By this movement the viscera of the abdomen are pushed obliquely downwards and forwards, as if 
towards the umbilicus, thereby diminishing the perpendicular depth of the abdomen whilst that of the thorax is proportionally 
increased. Now as the ribs are at the same moment drawn upwards by the action of the intercostal muscles, (Plate XXIII., 
fig. 1,) their lower margins being at the same time slightly everted by a sort of twisting motion which they sustain, and as the 
sternum is pushed forward somewhat by the tendency of the ribs to come more into a straight line with their cartilages, aided by 
the elasticity of the latter, which is brought into play, we can see at once how the capacity of the chest is increased in every 
direction, viz. from above downwards by the descent of the diaphragm, from before backwards by the protrusion of the sternum, 
and from side to side by the ascent of the ribs, and the eversion of their lower margins. This change in the capacity of the chest 
necessarily gives rise to a diminution of the pressure upon the organs which it contains, or, in other words, to a tendency to the 
production of a vacuum, and as the pressure remains undiminished upon all the other parts of the body, fluids will necessarily 
rush in and restore equilibrium. It is in this way that the atmospheric air is made to pass through the mouth and air-passages 
downwards to the lungs, and may be said to be sucked into their vesicles. The same principle applies to the flow of venous 
blood. We see that it is retarded in its passage whilst the chest is contracted during expiration and the capacity of the lungs 
diminished, and that this obtains even in the case of the blood which flows in the veins of the neck and face, where its descent 
is not a little assisted by gravity. Still it accumulates and swells them in the state just noticed; but as soon as the inspiratory 
effort commences, and the cavity of the thorax thereby becomes increased, the venous blood finds a free passage towards the 
heart, being literally pumped into the chest by a mechanico-hydraulic contrivance. 

The influence of the diaphragm upon the stomach and the other organs contained in the abdomen can be at once perceived, 
by paying a little attention to the sketch which is given of it, and of the muscles of the abdomen, in fig. 4, Plate XXVII. If, 
whilst the diaphragm descends in inspiration, the oblique and transverse muscles of the abdomen be made to contract, the con- 
tained organs will be placed between two compressing agents, which will assist materially their own contractile powers, in 
propelling their contents either downwards, as in the different expulsive efforts, or upwards, as in vomiting. 



PLATE XXV. 

The rectus muscle of the abdomen, 7, 8, and the transversalis, 9, 10, which are given in this drawing, have been already 
described in page 49. The flat thin muscle, 6, 6, which extends from the sternum to the ribs, and is in close apposition with their 
posterior or thoracic surface, requires to be briefly noticed. From its position, and the points to which its fibres are fixed, it may 
be termed sterno-costal, but is ordinarily named the triangular muscle of the sternum, (m. triangularis sterni ;) it is thin and 
flat, and composed of a mixture of tendinous and fleshy fibres, the inner extremity of which is attached to the ensiform cartilage, 
and to the margin of the sternum as high up as the junction of the fourth costal cartilage, sometimes a little higher, whilst the 
outer end or insertion is fixed to the cartilages of the ribs, from the sixth to the third, or the second, as in the present case, forming 
thereby a series of points or digitations. The power of this muscle is necessarily very limited; its most obvious action is that 
of depressing or drawing down the cartilages of the ribs, by which means it assists in expiration. 



PLATE XXVII. 

The five figures given in this plate are to be considered merely as sketches, or as diagrams employed in the illustration of 
the movement and actions of the diaphragm. The various points to which they refer have been sufficiently indicated in the 
remarks made upon the action of the diaphragm, (pp. 51, 52,) and in the references given at the foot of page 51. 



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53 



PLATE XXVIII. 

This drawing is intended to represent the different layers of muscles which enclose and support the abdominal viscera. 
Instead of looking at them layer after layer, as they are seen ordinarily in dissection, and as they have been exhibited in the 
preceding plates, their relations to one another are here shown by means of a transverse section carried through the whole body 
about the middle of the lumbar region. When this was effected, all the viscera were removed, and a drawing made of the soft 
parietes of the abdomen. At the sides will be observed the fleshy part of the three broad muscles overlaying one another ; No. 
14, 14, is the external oblique muscle of each side ; 15, 15, the internal oblique muscle : 16, 16, the transversalis. Each of these 
is found, when traced forwards, to terminate in a Avhite line which represents an aponeurotic membrane, which runs onwards 
from it to the fore part of the abdomen, where they all terminate, and become in a manner blended together, forming the linea 
alba, which we have previously described, (p. 47.) The white structures here noticed will be observed to form a sheath at each 
side which encloses the corresponding rectus muscle, 13, 13. The aponeurosis of the internal oblique muscle. 19, 19, on reaching 
the external border of the rectus, divides into two layers, 20, 20, which separate and diverge so as to leave between them an 
elliptic interval, which lodges the muscle. This aponeurosis it is which forms the immediate investment for the muscle just named. 
That layer of it, however, which passes in front of the rectus is further strengthened by the aponeurosis of the external oblique 
muscle, 18, 18, with which it becomes intimately united, so that their separation by dissection is rendered impracticahle ; ami 
again, the deep-seated layer of the internal oblique, which passes behind the rectus, joins with and is strengthened by the apo- 
neurosis of the transversalis muscle, 21,21. At the inner margin of the recti muscles these different layers of aponeurosis 
coming from both sides will be observed to unite together at the linea alba, No. 11. The inside of the transversalis muscle is 
lined throughout by the serous membrane called peritoneum ; towards the lower and fore part of the cavity it is supported by a 
thin layer of very different structure, called " fascia transversalis," which lying between the muscle and the peritoneum, repre- 
sents a lining calculated to strengthen the abdominal parietes at the lower part, and to lessen the liability to intestinal protrusions. 
Between the layers of muscles, as here shown, two lines or interstices are observed, indicating the separation between them. 
This is effected by means of a thin stratum of cellular tissue, which is in intimate contact with each of the contiguous surfaces. 
Outside the external oblique muscle is a layer of cellular and adipose tissue, 17, 17, interposed between it and the common 
integument, 10, 10, from which circumstance it is commonly termed the sub-cutaneous cellular tissue. In some cases the quantity 
and thickness of this deposit are considerable, which is the case in the present instance ; in others it is very thin, and contains no 
fatty matter. It may be traced upwards and downwards, forming a continuous layer all over the body : but in some places it 
becomes condensed or compressed into the form of a membranous layer, more or less firm ; it is then named the " superficial 
fascia :" whilst in others it resembles a deposit intended to fill up interstices, viz. between muscles, in the ham and axilla. 

Now at the posterior edges of two of these muscles certain aponeurotic layers are seen to extend backwards towards the 
spine, and to form connexions with it in such a way as to complete the circuit which encloses or circumscribes the abdominal 

PLATE XXVIII. 

No. 1. The lower surface of one of the lumbar vertebrae. 2. The vertebral foramen. 3, 3. The root and apex of the spinous process. 
4 4. The transverse processes. 5, G. The crura of the diaphragm cut across where they lie upon the interval between this vertebra 
and the one beneath it. 7, 7. The psoas muscle at each side cut across. 8, 8. The middle line of the body, corresponding in front to 
the linea alba, and behind to the lumbar spines. 9, 9. The integument covering the lower part of the loins and nates. 10, 10, 10, 
10, 10, 10. The cut edge of the skin all round the trunk. 11. The linea alba, formed by the junction of the aponeuroses of the two 
oblique and transversalis muscles. 12, 12. The cavity of the abdomen deeply shaded to indicate its vacuity. 13, 13. The two recti 
muscles, lying one on each side of the linea alba, enclosed within their aponeurotic sheaths. 14, 14. The external oblique muscle of 
each side. 15, 15. The internal oblique muscle. 16, 16. The transversalis muscle. 17, 17. The layer of subcutaneous cellular and 
adipose substance interposed between the skin and the muscles. 18, 18. The aponeurosis of the external obliqoe muscle continued 
forwards to the linea alba. 19, 19. The aponeurosis of the internal oblique muscle. 20,20. The two lamella! into which this 
aponeurosis divides in order to enclose the rectus muscle. 21, 21. The aponeurosis of the transversalis muscle, prolonged inwards to 
the middle line behind the deeper seated layer of the aponeurosis of the internal oblique muscle, with which it becomes united. 2 
The posterior or lumbar aponeurosis of the transversalis muscle at each side. 23, 23. The two layers into whi.-h this aponeurosis 
divides so as to forma sheath for 24, the quadratic lumborum muscle. 25, 25. Part of the latissimus dorsi muscle at e icb side, cut 
across by the transverse section which has been made. 26, 26. The aponeurosis of the latissimus muscle continued back to Ike dp of 
the spinous process. 27, 27. The mass of the lumbar muscles, viz. sacro-lnmbalis, longissimus dorsi, multifidus spil when 

divided by a transverse incision. 



54 

cavity. Here too a sheath is formed at each side by the aponeurotic prolongations which enclose a muscle (24,) constructed upon 
the same general principle as that which at the fore part surrounds the rectus; but there are points of difference which deserve 
notice. In the first place, the external oblique muscle has nothing to do with it, inasmuch as it terminates at the back part 
towards the lumbar region by a free margin which is altogether muscular in its structure, and consequently has no connexion 
with the aponeurotic bands which form the sheath just alluded to ; secondly, the immediate investment of the muscle consists in 
this case of lamella? given off from the transversalis muscle, and not from the internal oblique ; lastly, it is much thinner, and its 
fibres are not so well developed as in the sheath of the rectus. The formation of the sheath may be thus stated : — the aponeu- 
rosis given off from the posterior edge of the transversalis muscle, 22, divides into two layers, 23, 23, at the outer edge of the 
quadratua lumborum muscle, 24, one passing anterior to it, and the other posterior; the former is prolonged inwards towards the 
spine, and becomes fixed near the root of the transverse process, 4, of each lumbar vertebra, whilst the other passes behind it, 
and reaches the apex of the transverse process. It is in the interval left between these two layers that the quadratus lumborum 
muscle is lodged. Now the posterior layer is intimately connected with the aponeurosis given off from the edge of the internal 
oblique muscle, and the latter in its turn contracting an adhesion to the aponeurosis of the latissimus dorsi muscle, is conjointly 
with it, continued backwards in the form of a strong aponeurotic lamella, 26, which will be observed to reach the apex of the 
spinous process, No. 3, and there to be fixed. Between the lamella just noticed and that of the transversalis which goes to the 
apex of the transverse process, a considerable interval necessarily exists, which is filled up by the mass of the lumbar muscles. 



PLATE XXIX. 

The quadratus muscle of the loins, 23, 23, exhibits some analogy to the scalenus in the neck, in so far as it bears the same 
relation to the last rib which the scalenus does to the first. The latter, from its points of attachment, may be termed the "costo- 
transverse" muscle, and the quadratus may be named " ilio-costal." Two muscles of this name will be observed to lie one at 
each side of the lumbar part of the spine, and to extend from the crest of the ilium, its posterior fifth, to the lower edge of the 
last rib, which constitute its fixed points, or, in other words, its origin and insertion. Its fibres incline inwards a little as they 
ascend ; it is flat, pretty thick, and quadrilateral in its form, as its name implies. Its origin is effected by short aponeuroses, some 
of which will be observed to come not only from the ilium, but from the ilio-lumbar ligament; those which form its outer border 
pass upwards to the last rib, but those at the inner margin form four processes or points, which are attached by short aponeuroses 
to the summit of the transverse processes of the four upper lumbar vertebras. In the drawing the anterior surface of the quad- 
ratus appears to be in immediate apposition with the psoas which lies in front of it, whilst its posterior surface appears to rest 
upon the mass of the lumbar muscles, 24, 24, that lie behind it ; but it will be recollected that this muscle is enclosed in a sheath 
formed by the posterior aponeurosis of the transversalis muscle, (Plate XXVIII., Nos. 23, 23,) one lamella of which passes before 
it interposed between it and the psoas, whilst the other lies behind it and separates it from the lumbar muscles. 



PLATE XXIX. 

The muscles which lie at the sides of the lumbal part of the spine, and along the brim and fore part of the pelvis, are here exhibited, viz. 
the quadratus lumborum, the psoas major and minor, and the iliacus. As these muscles are deeply seated, being concealed by the 
abdominal viscera and their investing membrane, the quadratus being moreover covered by a special investment derived from the 
transversalis muscle, (Plate XXVIII., No. 23,) and the iliacus also by a special membrane, called fascia iliaca,— all these organs and 
structures must necessarily be removed, in order to bring the muscles fairly into view. 

Nos. 1,1. The eleventh rib at each side. 2, 2. The twelfth rib. 3, 4. The eleventh and twelfth dorsal vertebrae. 5, 6, 7, 8, 9. The five 
lumbar vertebrae indicated in their order from above downwards. 10. The junction of the fifth lumbar vertebra with the top of the 
sacrum, forming a projecting angle, (sacro-vertebral,) and commonly termed the promontory. 11. The anterior concave or curved 
surface of the sacrum. 12, 12. The crest of the iliac bone at each side. 13. The great trochanter of the thigh-bone at the right side. 
14. The upper part of the shaft of the right thigh-bone. 15. The ischium. 16, 16. The body of the pubic bone at each side. 17. 
The symphysis, or junction of these bones. 18, 18. The great psoas muscle at each side, (prelombo-trochantinien, Chauss.) 19. The 
small psoas of the left side, (psoas parvus.) 20. Its tendinous insertion into the ilio-pectineal line ; this muscle sometimes does not 
exist. 21, 21. The iliacus muscle of each side, where it rests upon the anterior or hollowed surface (fossa,) of the iliac bone. 22,22. 
The junction of the iliacus with the psoas at each side, by which means they become united into one previous to their insertion into the 
small trochanter of the thigh-bone. 23. The quadratus lumborum muscle. 24, 24. Part of the lumbo-dorsal muscles lying behind 
the quadratus. 25. Part of the sartorius muscle of the thigh. 26. Part of the rectus muscle. 27. The tensor muscle of the thigh, 
(tensor vaginae femoris.) 28. The fascia where it corresponds with the upper and outer part of the hip, forming an investment for the 
gluteus medius muscle. 29. Part of the pectineus muscle. 30. Part of the Ion"- adductor muscle. 



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55 

Actions. — The most obvious action of this pair of muscles is that of drawing down the last rib at each side, and rendering 
it fixed. When this is effected, the last intercostal muscle can be made to act upon the eleventh rib and depress it, which 
movement can be propagated simultaneously to the other ribs, by means of the intercostal muscles, so that all of them are 
together drawn downwards, and the capacity of the chest diminished. Thus the quadratus muscle may be made to commence 
a series of movements, all tending to effect a forcible expiration. Again, the separate points by which these muscles are fixed to 
the transverse processes of the lumbar vertebrae enable them to act upon the spinal column, so as to incline it now to one side, 
now to the other, or to steady and fix it when both act together. Their power in these particulars is not a little increased by their 
connexion with the last ribs, which may be regarded as two lengthened transverse processes, affording a longer lever with a propor- 
tionate increase of mechanical power to be directed upon the spine itself. 

The great psoas, and the iliacus muscles, 18, 21, may be regarded as a single muscle, inasmuch as they are united, 22, pre- 
viously to their insertion ; but the more usual practice is to describe each separately. The great psoas muscle, (psoas magnus,) 
No. 18, lies along the sides of the lumbar vertebras, crosses the brim of the pelvis, and then descends into the thigh. It is therefore 
of considerable length, inasmuch as it reaches from the last dorsal vertebra to the small trochanter of the thigh bone, and may, 
if it were necessary to resort to much rigour in its description, be considered as divisible into three parts, which are here seen at 
a glance, viz. the lumbar, the pelvic, and the femoral. Its form is elongated, its anterior surface being rounded and convex, the 
posterior being compressed and flat ; it tapers towards its extremities. Its fibres will be observed to arise by short aponeuroses 
from the sides of the bodies of the last dorsal vertebra, and of the four upper lumbar, also from the intervertebral fibro-cartilages ; 
another set, more deeply seated, will be found attached to the transverse processes of the four lumbar vertebras. The fibres of 
the muscles thus derived pass downwards, and altogether form a rounded thick fasciculus, which, passing over the brim of the 
pelvis, inclines outwards, downwards, and backwards, passing deeply into the upper and fore part of the thigh, where it is fixed 
to the small trochanter. The fleshy fibres of the psoas become fixed from point to point to the surface of the tendon, which 
is at first concealed between them, but afterwards becomes apparent towards the outer and fore part of the muscle, where it also 
gives attachment to a considerable number of the fibres of the iliacus, 22, 22. The anterior surface of the psoas corresponds 
at its upper extremity with the diaphragm, Plate 26, with the kidney and supra-renal capsule, with the smaller psoas when it 
exists, and the iliac fascia which covers it ; with the femoral or crural arch, and the commencement of the femoral artery. The 
inner surface corresponds above with the spinal column, and lower down with the great iliac vessels. 

The iliac muscle, 21, 21, (M. iliacus; iliaco-trochantinien,) is so called from its relation and points of attachment to the 
ilium. The epithet " internal," or " anterior," is very commonly applied to it, which is no longer necessary, as the relative term 
" posterior," or " external," is no longer applied to any muscle. The pyriformis was at one time known as the posterior, or 
external, iliac muscle. The iliacus derives its form in a great degree, as well as its name, from the iliac bone, whose hollow or 
fossa it fills up ; hence it is broad above, consisting of radiating fibres, and narrowed towards its lower extremity. It arises by 
short aponeuroses from the inner margin of the crest of the ilium, (its anterior two-thirds,) from the inner edge of the anterior 
spinous processes of the ilium, (superior and inferior,) and from that of the curved border of the bone between these points, also 
from the concave surface of the ilium by a great number of fleshy fibres, which are fixed to its upper three-fourths, and some are 
found attached to the broad part of the ilio-lumbar ligament. The fibres will be observed to incline inwards as they descend, 
and most of them become fixed to the outer edge of the tendon of the psoas. The fibres which correspond with the outer border 
of the iliacus descend lower down than the rest, and are inserted into the curved line which leads from the small trochanter of 
the thigh bone to the rough ridge on its back part, (linea aspera.) The anterior surface of this muscle is covered by the iliac 



PLATE XXX. 

Back and front views of the fascia of the thigh and leg are here given. The subjacent muscles are to a certain extent seen through it, the 
numbers indicate their position. 

Fig. 1. No. 1. The anterior superior spinous process of the ilium. 2. The pubes. 3. Poupart's ligament. 4. The external abdominal 
ring with the spermatic cord passing through it. 5. The part of the fascia which covers the tensor vagina; muscle, (i. The inner part 
which conceals the pectineus muscle. 7. The curved margin of the aperture [foramen saphenum] in the fascia for the transmission 
of the superficial vessels. 8. The lower part of the aperture where the vein enters. 9. The adductor longus. 10. The sartorius. 1 1. 
The rectus femoris. 12. The vastus externus. 13. The vastus internus. 13*. The fibres of the fascia passing upon the patella and 
its ligament; lower down they become attached to the head of the tibia, and finally continuous with that which covers the leg. 1 1. 
The fascia covering the tibialis anticus muscle. 15. The peronei. 16. The gastrocnemius. 17. The tibia. 18. The anterior annular 
ligament of the ankle. 19. The thin part of the fascia covering the extensor tendons upon the dorsum of the foot. 

Fig. 2. No. 1. The crista of the ilium. 2. Part of the tendinous structures which cover the side of the sacrum. 3. The part of the fascia 
which conceals the gluteus medius muscle. 4. The gluteus maximus; here it is very thin, and the coarse fibres of the musclee are 
distinctly seen through it. 5. The position of the vastus externus. 6. The biceps flexor. 7. That of the semi-tendinosos and semi- 
membranosus. 8. The fascia stretched from the flexor muscles so as to cover in the popliteal space. 9, 9. The fascia where it covers 
the muscles of the calf of the leg and their tendon. * 



50 

fascia ; is crossed by the crural arch, and lower down by the sartorius and pectineus muscles ; its posterior surface rests on the 
iliac fossa, the brim of the pelvis, and the capsular ligament of the hip joint ; its inner border, which is in close apposition with 
the psoas, is however separated from it by the anterior crural nerve, which is lodged in the groove between them. 

As these muscles conjointly slide over the brim of the pelvis and the capsule of the hip joint, and as a free and easy motion 
is necessary in this situation, provision for this purpose has been made. A synovial sac of considerable extent lies between the 
posterior surface of the muscles and the parts just named, which secretes a lubricating fluid, and by its looseness admits of every 
movement that can be required. 

The small psoas muscle, (psoas parvus, No. 19,) when it exists, which is not always the case, extends from the last dorsal 
vertebra to the brim of the pelvis resting upon the great psoas muscle. It is a flat thin fasciculus, composed in the upper third 
of its length of fleshy fibres, the rest being a narrow tendon. It arises by short aponeurotic fibres from the body of the last 
dorsal vertebra, and from the intervertebral substance which connects it with the first lumbar ; and its tendon is fixed to the ilio 
pectineal eminence, where it will be observed to widen previously to its termination. 

Actions. — When the psoas and iliacus muscles of one side act together and take their fixed points above, they bend the 
thigh upon the pelvis, and at the same time rotate it outwards. This they are enabled to do by their passing so far backwards, 
and by the curve which they make previously to their insertion, as well as by the mechanical advantage which their connexion 
with the trochanter minor gives them. When the thigh bones are fixed, so that the muscles of both sides are enabled to act from 
below, they can be made to concentrate their force upon the spine and the pelvis, and when the muscles of opposite sides act 
together, they draw the spinal column forwards, and by continuing their effort become powerful agents in maintaining the body 
erect upon the legs. In the effort of standing on one leg also the psoas and iliacus act with great power in maintaining the pelvis 
and the spinal column erect, and in a manner poised upon the head of the thigh bone. 

At the outside of the psoas, and in part overlaid by it, is a muscle (23, 23) of a very different form, being flat and com 
pressed. This, from its shape and position, is usually called the square muscle of the loins, quadratus lumborum ; and from its 
points of attachment it is sometimes named ilio-costalis, as it is fixed below to the ilium, No. 12, and above to the last rib, 2. It 
is situated deeply in the lumbar region close to the vertebral column, and is of an irregular quadrilateral form, being broader 
below than above. It arises by tendinous fibres from the crista of the ilium for about one-fourth of its extent, and is inserted 
into the inferior border of the last rib for about half its length, and by four tendinous points into the transverse processes of the 
four superior lumbar vertebrae. This muscle is enclosed in a sheath, {sheath of the quadratus,) not unlike that of the rectus, 
but not so dense or firm in its structure. The posterior or lumbar aponeurosis of the transversalis muscle divides into two layers 
near the border of the quadratus, one of which is prolonged backward behind the latter muscle, to be attached to the apices of 
the transverse processes of the lumbar vertebras, and the other before it, to be fixed at the roots of these processes. Now, the 
lower border of this layer is attached to the inner margin of the crista ilii, (its posterior fourth,) and the upper one is stretched 
across from the anterior surface of the last rib to the root of the transverse process of the first lumbar vertebra. This latter part, 
from its mode of attachment and relation to the broad muscle of the diaphragm, has been named by some ligamentum arcuatum 
externum. 

The relation of this muscle to its sheath, and the mode in which this investment is formed, will be seen at once by referring 
to Plate XXVIII., where 24 is the quadratus, and 23, 23, the two layers of the sheath. 



PLATE XXX. 

These drawings are intended to exhibit at one view a structure which forms the immediate investment of the muscles of the 
lower extremity. The outline of the muscles is indicated so as to convey to the mind the idea that they are covered by a thin 
veil drawn tightly upon them, allowing their form to be seen, but obscuring their colour and intimate texture. Most of the num- 
bers are placed so as to indicate the position of the muscles as they lie under the membrane. 

When the. common integument has been dissected off and removed from the lower extremity, it will be found invested by 
another membrane of quite a different structure, being of a glistening white colour, close in its texture, and composed of fibres 
crossing in various directions. Anatomists have classed it amongst the fibrous membranes, and named it the broad swathing 
band, fascia lata, of the thigh. The leg is enclosed in a similar investment, and so is the foot. But each presents certain pecu- 
liarities, which require a separate consideration. 

The fascia lata of the thigh may be considered as a special or immediate investment, which not only encloses it in its entire 
extent from the knee to the pelvis and Poupart's ligament, but also sends processes inwards in several situations, forming 
partitions between the muscles. The thickness of this membrane varies in different parts. It is considerable along the external 



57 

side of the thigh, where it lies upon the vastus externus muscle, fig. 2, No. 5, and higher up upon the gluteus medius, No. 3 ; it 
is. less so on its posterior aspect over the flexor muscles, fig. 2, No. 6, 7 ; but superiorly, and at the inner side, it is in some places 
so thin as to require great care in dissecting off the skin, else the fascia will be removed with it. When examined towards the 
lower part of the thigh, it is found to be prolonged over the knee-joint, and to be continuous with the fascia of the leg. It has at 
the same time a connexion more or less intimate with all the bony prominences round the articulation, viz. with the condyles at 
each side ; with the patella, 13, and its ligament, in front ; with the tuberosities of the tibia below ; with the head of the fibula to 
the outer side, to which it is guided by the biceps muscle ; and finally, after being stretched across the popliteal space, fig. 2, 
No. 8, it is prolonged over the gastrocnemius muscle, fig. 2, No. 9, and so becomes blended with the fascia of the leg at the 
back part. 

When traced upwards, over the thigh, it is found not only to encase it, but also to send processes inwards between the muscles. 
The most dense and remarkable of these is one which passes in between the vastus externus and the short head of the biceps, fig. 
2, No. 6, and is attached to the linea aspera in its whole length, as far as the insertion of the gluteus maximus. Along the 
internal side of the thigh it invests the muscles, and merely gives attachment to some thin cellular lamella?, which lie between 
them; but along the course of the sartorius, fig. 1, No. 10, particularly in the lower two-thirds of its extent, an investment or 
sheath is formed for it, which serves to maintain it in its place, notwithstanding the obliquity of its direction. 

Its points of attachment at the superior part of the limb are so numerous, that it becomes necessary to examine each of them 
in detail. Thus, externally, after having been intimately connected with the insertion of the gluteus maximus, it is prolonged 
backwards and upwards on the cutaneous surface of that muscle, fig. 2, No. 4 ; and though very thin and weak, it may with 
care still be traced as far as to the side of the sacrum and coccyx, and also to the crista of the ilium, to which it is firmly attached, 
after having passed over the upper part of the gluteus medius, fig. 2, No. 3. The fascia in the latter situation becomes very dense 
and firm, and is intimately connected with the fibres of that muscle. Still more externally, it divides into two lamella?, which 
embrace the inferior termination of the tensor vaginae femoris, fig. 1, No. 5, to which it in this manner gives insertion. These 
two lamellae become united into one along the posterior border of the muscle, which, by being prolonged over the gluteus medius 
(to whose fibres it gives attachment by its inner surface,) passes to be inserted into the crista of the ilium and its spinous process. 
Along the inner side of the thigh, the fascia passes upwards over the adductor muscles, fig. 1, No. 9, and becomes attached to the 
tuberosity of the ischium and its ramus, as well as to that of the os pubis, as far as its spinous process. The most important 
part of the membrane — that which has claimed the greatest share of attention from anatomists and surgeons, remains now to be 
considered, namely, the part immediately below Poupart's ligament, and which extends from the spinous process of the ilium to 
that of the os pubis. 

It will be recollected that the membrane forms an uninterrupted sheath for the limb, until it comes within a little more than 
an inch of Poupart's ligament, fig. 1, No. 3. There a division takes place, and an opening is established for the transmission of 
the superficial vessels. The superficial vein, (vena saphena,) in its whole course, from the inner ankle to the knee, and thence to 
the top of the thigh, lies superficial to the fascia. The superficial lymphatic vessels are similarly situated ; the superficial epigastric 
vessels also descend over the abdominal muscles ; and as all these converge to one point, in order to communicate with the deep- 
seated vessels, an opening must be established for them in the fascia lata. The existence of this opening, (fig. 1, No. 8,) has 
caused a division of the anterior portion of the fascia into two parts, one external, the other internal. 

The external or iliac portion passes upwards, lying on a plane anterior to the vessels, and becomes blended with the lower 
border of Poupart's ligament, with which it continues to be thus united as far as the spinous process of the pubes. Whilst it is 
being prolonged in front of the femoral vessels, this part of the membrane, by reason of its inclination from below upwards and 
inwards, must necessarily present a curved or falciform appearance, fig. 1, No. 7, one extremity of it being at the lower border of the 
opening, the other at the spinous process of the pubes. Now, as the membrane stretches between these two points, its border 
becomes folded on itself, not ceasing abruptly at the margin of the opening, as at first sight may appear. On the contrary, it is 
reflected on itself, and the reflected part becoming very thin, and degenerating into cellular tissue, passes outwards on the sheath 
of the deep femoral vessels, with which it is identified ; but towards its superior termination it turns under the border of Poupart's 
ligament, and adheres to that of Gimbernat, with which it is inserted into the pectineal line.* 

The pubic or inner portion of the fascia, fig. 1, No. 6, so called from its situation, lies on the pectineus muscle, and therefore 

* The fascia lata is more commonly described, in the schools of this city, as having its origin from the pelvis and running down upon the lower extremity ; 
and not its insertion there, as described in the text. Its external or iliac portion is called the sartorial, its internal or pubic, the pectineal, from the muscles wfaiob 
they respectively cover. The inner part of the sartorial, which is stretched along Poupart's ligament to the spine of the pubis, presents a crescentic edge down- 
wards and inwards, and has been called in consequence by Allan Burns, the falciform process of the fascia lata. The internal termination of this falciform 
process, called Hey's ligament, or the femoral ligament, is folded as stated in the text, or half twisted on itself so as to present a cutting edge obliquely down- 
wards; it crosses the crural ring in close connection with the sheath of the vessels, and running backwards is attached to the pubis just in front of Gimbernat's 
ligament, where it is continuous with the pectineal or inner portion of the fascia lata. Hey's ligament is considered a frequent seat of stricture in crural hernia ; 
but in several cases where I have operated for crural hernia, with stricture at this point, the cause of strangulation has appeared to me to be rather in the thickening 

of the sheath of the vessels below the ligament than in the ligament itself. For a fuller account of the fascia, see Pancoast's Wistar, or Horner's Anatomy J. P. 

Musclks. — 8 



58 

is on a plane posterior to the femoral vessels. Superiorly it terminates at the pectineal line, to which it is guided, as it were by 
the muscle of that name ; externally, it passes behind the vessels and their sheath, and, on reaching the border of the psoas muscle 
and its tendon, divides into two lamellae. Of these, one, rather dense and firm, passes deeply behind the tendon, and becomes 
attached to the fibrous capsule of the hip-joint ; the other, lying more superficially, unites, along the border of the psoas ma<mus 
with a membrane covering the muscle just named. This cannot be the fascia iliaca, as is usually stated. That membrane extends 
no farther than Poupart's ligament, in all that part between the spine of the ilium and the femoral vessels. In the rest of its 
extent, it forms part of the sheath of these vessels, behind which the pubic part of the fascia lata lies. The membranous structure 
then, with which the pubic part of the fascia lata becomes blended at the border of the psoas, is a deep-seated layer of the fascia 
lata, prolonged upwards upon the iliacus and psoas muscles, and which finally unites with the under surface of the fascia iliaca 
» where the latter turns forwards to be connected with Poupart's ligament. 

The iliac and pubic parts of the fascia lata are continuous, and united at the lower border of the opening, which their junction 
serves to form, and over which slides the saphenous vein. Though the fascia, in the situation here referred to, appears to present 
a defined concave border, (the concavity looking upwards,) fig. 1, No. 8, it still will be found not to cease abruptly; on the contrary, 
it is folded on itself like the external margin of the opening, and reflected down on the sheath of the vessels, on which it is gradually 
lost. The oval aperture here described, from its transmitting the superficial vein, (v. saphena,) is called the saphenous opening, 
(foramen saphenum ) of the fascia lata.* 

The lower part of the limb, from the knee to the ankle, is encased by a membrane similar in structure and use to that of the 
thigh. Posteriorly it is continuous with that part of the latter which covers the popliteal space, fig. 2, No. 6, S ; externally it 
contracts a firm adherence to the head of the fibula, where it is strengthened by additional fibres, sent down by the biceps muscle- 
and internally it receives an expansion from the sartorius. If traced down from these different points, the fascia will be found to 
invest the muscles, and also to send processes inwards between them, more particularly between the extensor communis and 
tibialis anticus (fig. 1, No. 14,) in front, and on the outside between the peroneal muscles, fig. 1, No. 15. These intermuscular 
septa serve to increase the number of points to which the muscles are attached ; for it will be observed that their fibres arise from 
them, as well as from the inner surface of the fascia, for some way down the leg. The fascia is thin posteriorly over the 
gastrocnemius, fig. 2, No. 9 ; but is dense and firm where it covers the extensors, more particularly at the upper part ; and will 
be found so firmly united along the anterior edge of the tibia, fig. 1, No. 17, that it cannot be detached so as to be traced over its 
cutaneous surface. If traced along the posterior aspect of the leg, the fascia will be observed to pass over the tendo Achillis, and 
to be connected with the malleoli at each side, and also with the fibrous sheaths which bind down the tendons passing behind 
them. At the inner side it joins the internal lateral ligament ; externally it is continuous with the fascia covering the side of the 
foot, and in front becomes identified with the anterior fasciculus of the anterior annular ligament, fig. 1, No. IS. 

The fasciae of the foot consist of two parts, differing in density and texture as well as in situation, one being a dense fibrous 
structure, placed in the sole of the foot, the other a thin membrane covering its dorsum. Previously to examining the latter it 

PLATE XXXI. 

The superficial muscles at the front of the thigh are shown in Fig. 1, and those which lie deeply in Fig. 2. 

Fig. 1. No. 1. The anterior superior spinous process of the ilium. 2. The pubes. 3. Part of the aponeurosis of the external oblique 
muscle of the abdomen. 4. The lower border of this aponeurosis, forming Poupart's ligament. 5. The tensor vagina muscle— its 
fleshy part. 6. Its lower extremity, where it is inserted into the fascia lata. 7. Part of the gluteus medius still covered by the fascia. 
8. The sartorius muscle. 9. Its aponeurosis, where it spreads over the tendons of the gracilis and semi-tendinosus muscle previously 
to its insertion. 10. The erectus femoris muscle. 11. Its tendon. 12. The patella. 13. The ligament of the patella 14 Its 
insertion into the tubercle of the tibia. 15. The vastus externus muscle. 16. The vastus internus. 17. The psoas and iliacus 
muscles. 18. The pectineus. 19. The adductor longus. 20. The gracilis. 

Fig. 2. No. 1. The crista and anterior superior spinous process of the ilium. 2. The anterior inferior spinous process 3 The iliac 
fossa. 4. The ilio-pectineal eminence. 5. The upper surface of the os pubis. 6. Its angle. 7. The capsular ligament of the hip-joint 
covering the head and neck of the femur. 8. The trochanter major of the femur. 9. The trochanter minor. 1 0. The shaft or body of 
the femur. 11. Its inner condyle. 12. The outer condyle and tuberosity. 13. The adductor brevis muscle. 14. The adductor 
longus. 15, 15. The adductor magnus— its broad fleshy part forming a flat plane behind the two other adductors, which appears both 
above them and below them. 16. Its tendon, which is prolonged to the tuberosity upon the inner condyle. 17. The external obturator 
muscle. 18. The quadratus femoris muscle appearing just above the upper border of the adductor magnus, (15,) a slight fissure 
intervening. & > v. v b 

* Over this oval aperture, called by Scarpa the fossa ovalis, is spread in front of the sheath of the vessels a delicate fascia called the cribriform layer of the 
fascia lata; this connects the crescentic edge of the falciform process (which is never sharply defined except by the knife of the anatomist) with the pectineal 
portion of the same fascia lata. — J. P. 



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59 

becomes necessary to describe a band of fibres which is strained across the bend of the ankle, and serves to bind down the tendons 
of the muscles. 

The anterior annular ligament, fig. 1, No. 18, is attached by one extremity to the external malleolus and to the depression 
on the upper surface of the calcaneum, from which points the fibres of which it consists pass obliquely inwards, and divide into 
two fasciculi on reaching the border of the peroneus tertius and common extensor, one of them passing in front, the other behind 
the tendons of these muscles. At their inner border the fasciculi become united again, thus forming a tube or sheath for the 
transmission of the tendons. A similar arrangement of these fasciculi obtains as they cross the tendons of the extensor proprius 
pollicis and tibialis anticus, so that each is made to pass through a separate tube ; and, finally, the fibres of the ligament, after 
having been thus successively separated and united again, are inserted into the internal malleolus. Now, the fasciculus of this 
band, or ligament, which lies in front of the tendons, is continuous by its upper border with the fascia of the leg, and by the lower 
with that on the dorsum of the foot, all three lying on the same plane beneath the skin. The internal annular ligament is 
attached, by one extremity, to the inner malleolus and the fibrous sheath of the muscles passing behind it, by the other to the 
inner margin of the calcaneum. Its superior border is continuous with the fascia of the leg, the inferior gives origin to part of 
the abductor pollicis ; one surface is subcutaneous, the other is in contact with the vessels and tendons of the flexor muscles, 
which pass under cover of it into the sole of the foot. 

The fascia on the dorsum of the foot, fig. 1, No. 19, is a thin lamella which covers the extensor tendons, being prolonged 
from the lower border of the annular ligament forwards to the digital phalanges. When traced towards the external border of 
the foot, it is found to be attached to the head of the fifth metatarsal bone. Behind this point it becomes blended with the cor- 
responding margin of the plantar fascia, and before it, the membrane folds over the abductor and short flexor of the little toe, and 
unites with the digital process of the plantar fascia that lies beneath them. When traced along the inner border of the foot, we 
find the membrane passing over the fleshy fibres of the abductor pollicis. Posteriorly, it is attached to the calcaneum ; but in 
all that part called the hollow of the foot, after covering the muscle just named, it is folded round its outer border, and, for part 
of its extent, passes deeply towards the tarsal bones, becoming blended with a septum sent upwards by the plantar fascia ; farther 
forwards it unites with the first digital process of the fascia just named. The examination of the fascia in this situation is easily 
conducted by dissecting it from the tarsal bones, and tracing it over the border and plantar surface of the abductor muscle, when 
its termination and attachments will be found to be as above stated. 

The plantar fascia is a dense fibrous structure, extended from the calcaneum to the heads of the metatarsal bones, along the 
sole of the foot. It is attached behind to the posterior tubercles on the plantar surface of the calcaneum, where its fibres (the 
greater number of which are longitudinal) are aggregated into a narrow thick fasciculus. From this point the fibres, as they pro- 
ceed forwards, diverge and arrange themselves into two parts, separated by a depressed interval, one corresponding with the 
muscles of the little toe, the other with the middle of the tarsus, and the whole width of the metatarsus. The external, or narrow 
part, after being connected firmly with the fifth metatarsal bone, sends forwards some thin fibres which unite with the last digital 
process of the larger portion. By its outer border it gives attachment to the fascia of the dorsum of the foot, from the inner it 
sends a process upwards which contributes to form a septum between the plantar muscles. The broad portion of the fascia 
becomes thin as its fibres diverge, and ultimately resolves itself into five processes corresponding with the metatarsal bones. Each 
process, on reaching the digital extremity of these bones, divides into two fasciculi, which separate and become attached to their 
sides, thus leaving an angular interval for the transmission of the tendons and vessels to the phalanges of the toes. From each 
border of this part of the fascia a membranous partition is given off, which separates the mass of muscles placed in the middle 
of the foot from those that are situated along its borders and belong to the great and little toes. 



PLATE XXXII. 

The muscles placed at the back of the hip are shown in these drawings just as they lie, layer after layer. At the right side, 
in fig. 1, the great gluteus muscle is brought into view by the removal of the skin and the fascia; at the left side of the same 
figure, the middle gluteus muscle, 14, of which part only is seen at the opposite side, is exposed by the removal of the great 
gluteus muscle. It is seen in its entire extent in Plate XXXIII. fig. 1, No. 13. Lower down are seen the external rotator muscles 
placed in a series one beneath the other, Nos. 16, 17, 18, 19, 20, 21. In fig. 2, in order to exhibit the third gluteus muscle, No. 9, 
the second muscle of that name is necessarily taken away : — We shall notice these separately. 

The great gluteus muscle, (m. gluteus maximus,) fig. I, No. 11, forms the prominence of the nates; its bulk and mass indi- 
cate ;it once the powerful action which it exerts. Its fibres are aggregated into thick and coarse fasciculi, and all are superficial, 
being covered merely by the skin and a thin layer of fascia. The direction of the fibres is oblique as they extend from above 



60 

downwards and outwards ; they are attached above to the pelvic bones, viz. the ilium, the sacrum, and the coccyx, by means of 
short tendinous fibres. The three attachments here indicated are marked in the drawing by three numbers, 11, 11, 11. The 
fleshy fibres will be observed to end in a broad tendon, No. 12, which slides over the great trochanter of the thigh-bone, and is 
fixed into a rough impression beneath it. The line of insertion of the muscle is indicated at the left side, No. 13*, where all the 
rest of the muscle is removed, its femoral attachment alone remaining. It will be observed that two of the borders of the 
muscle are fixed, and two are free and unattached, the upper one sliding in a manner over the gluteus medius, and the lower one, 
which forms the fold of the nates, overlaying the long flexor muscles, part of which is here shown. Where the gluteus slides 
over the great trochanter, provision is made for that degree of free motion which is necessary in this situation, by means of a 
large secreting membrane or synovial bursa, which lines the contiguous surfaces and enables them to slide smoothly one over the 
other. 

The middle gluteus muscle, (m. gluteus medius,) No. 14, is seen only in part until the great gluteus muscle is removed. When 
that is done, its lower part and its insertion, 15, are brought fully into view ; it is of considerable extent, and by its mass is enabled 
to act with great power. Its fibres will be seen to take their points of attachment above upon the ilium, where they are in a 
manner expanded and radiating ; they are fixed to almost every point of the crescent-shaped interval between the crest of the 
ilium and the origin of the third gluteus muscle, and which is shown in fig. 2, No. 8, where the bone is exposed by the removal 
of the muscle. The fibres of origin pass downwards and converge to a strong and broad tendon, No. 15, which is fixed into the 
upper border and external surface of the trochanter major. 

The third gluteus muscle, (gluteus minimus,) fig. 2, No. 9, lies close upon the bone in its entire extent, and it cannot be seen 
untii the others are removed ; it is broad and expanded at its upper part where it is composed of fleshy fibres, but it gradually 
narrows where its fibres run into a tendon, No. 10, previous to its insertion. It is fixed above to the external surface of the 
ilium, and below to the anterior border and outer surface of the trochanter major. 

According to that system of nomenclature which has been constructed on the principle of making the names of muscles 
express their points of attachment, the great gluteus muscle is called " Ilio-sacro-femoral," the next muscle of that name becomes 
the great " Ilio-trochanteric," and the third is the small " Ilio-trochanteric." 

Actions. — These muscles are enabled to act upon the femur and upon the pelvis according as the one or the other becomes 
relatively the more fixed point. When they act from above and concentrate their effort upon the thigh, they are enabled to draw 
it outwards, or in other words, they become abductors. The power of the great gluteus muscle in this particular is not a little 
increased by its being thrown outwards so far from the central line, where it slides over the great trochanter. Whilst executing 
this movement of abduction, the second and third glutei, by reason of the obliquity of their anterior and posterior fibres, are 
enabled to impress also a certain degree of rotatory motion upon the thigh-bone either forwards or backwards. Now, suppose 
the thighs to become the more fixed points, for instance in the standing posture ; these muscles act upon the pelvis, and if the 
body is bent forwards as in the stooping posture, the great glutei, by acting upon the pelvis, draw it backwards, and retain it and 
the body erect upon the thighs. The bulk of these muscles is characteristic of the human subject ; the only being which, in all 
particulars, is fitted to walk erect. 



PLATE XXXII. 

These drawings exhibit the different muscles which lie at the back of the pelvis. 

Fig. 1. No. 1. The back part of the sacrum covered by the aponeuroses of lumbar muscles. 2. The coccyx. 3, 3. The articulating pro- 
cesses of the last lumbar vertebra. 4, 4. Its transverse processes. 5, 5. The crista of the os ilium at each side. 6. The great sacro- 
sciatic ligament. 7. The tuber ischii. 8. The trochanter major. 9. The trochanter minor. 10. The shaft or body of the thigh-bone." 
11, II, 11. The great gluteus muscle, (m. gluteus maximus;) the references indicate its three attachments to the ilium, to the sacrum 
and coccyx, and to the great sacro-sciatic ligament. 12. The broad tendon in which the fleshy fibres of the great gluteus muscle end, 
and which, after sliding over the great trochanter, aTe inserted into the rough impression which lies beneath it. 13, at the right side, 
indicates the connexion between the insertion of the muscle and the fascia lata of the thigh; and 13,* at the left side, marks the lino 
of insertion of the muscle into the thigh-bone. 14, 14. The second gluteus muscle, (m. gluteus medius:) at the right side part of it 
only is seen, the rest being concealed by the great gluteus muscle ; but at the left side this portion is brought into view by the removal 
of the great gluteus muscle, part of the fascia which covers it is still left on at the upper third of its extent. 15. The tendon by which 
the gluteus medius is inserted into the trochanter major. 16. The pyriformis muscle. 17. The superior gemellus. 18. The obturator 
internus. 19. The inferior gemellus muscle. 20. Small part of the external obturator muscle, (m. obturator externus.) 21. The 
quadratus femoris muscle. 
Fig. 2. No. 1. The crista of the os ilium. 2. Its posterior superior spinous process. 3. The back part of the sacrum. 4. The great saero- 
sciatic ligament. 5. The small sacro-sciatic ligament. 6. The tuberosity of the ischium. 7. The trochanter major of the thigh-bone. 8. 
The broad part of the os ilium left uncovered by the removal of the gluteus medius muscle. 9. The third gluteus muscle, (m. gluteus 
minimus.) 10. The tendon by which it is inserted into the trochanter major. 11. The pyriformis muscle. 12. Its tendon. 13. The 
superior gemellus muscle. 14. The obturator internus muscle. 15. The inferior gemellus muscle. 16. Part of the obturator externus 
muscle. 17. Quadratus femoris. 



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61 

When the second and third glutei muscles take their fixed points below, and concentrate their effort upon their upper points 
of attachment, it is quite clear that they must influence the whole of the pelvis ; for whatever motion is given to any one of its 
pieces is necessarily propagated to the rest, as they are all bound together and articulated with one another immoveably. Thus, 
in the effort to stand on one leg, the thigh-bone being rendered fixed, these two muscles act upon the pelvis and draw it hi a 
manner outwards, so as to place it over the head of the bone, by which action they counterbalance the weight of the trunk, and 
maintain it erect upon the limb. Suppose this to be done at the left side, and the body be made to rest upon the left leg for an 
instant, if it be intended to advance a step, then the right leg will be carried, or in a manner swung forwards ; the pelvis, and 
through it the whole body, being made to move as it were upon a pivot placed in the left hip joint. When in its turn the right 
leg is fixed upon the ground, the left is carried forwards in a similar manner, and the rotatory motion coinciding with its advance 
takes place in the right hip joint. In this way the centre of motion is changed from one joint to the other, and the sides of the pelvis 
are made to describe curves as they are alternately carried forwards in progression. It is this alternation of action in the muscles 
of opposite sides, and this change of the centre of motion from one joint to the other, which gives to the pelvis that sort of 
rotatory movement so perceptible in persons who walk irregularly, and which is so obvious in females in consequence of the great 
breadth of the pelvis. 

External Rotator Muscles. — In figs. 1 and 2, Plate XXXII. ; and in fig. 1, Plate XXXIII. , six small muscles will be observed 
extending from the pelvis outwards to the upper part of the thigh-bone. They are all deeply seated, being concealed by the 
great gluteus muscle. These conspire in their action upon the thigh-bone; for they draw the great trochanter, No. S, towards 
the tuberosity of the ischium, 7, as will be seen by referring to fig. 1 ; but as the neck of the bone prevents a direct approxima- 
tion, a rotatory motion is given to its shaft, by which the whole limb is turned outwards, hence these muscles are named the 
external rotators of the thigh. 

The pyriform muscle, (m. pyriformis; pyramidalis,) fig. 1, No. 16; fig. 2, No. 11, is seen immediately below the border of 
the second gluteus muscle ; it is tapering in its form, a fact which is expressed by its name. Its upper part or origin lies within 
the pelvis, its fibres being attached to the anterior surface of the sacrum, as may be seen by referring to Plate XXXIII., fig. 2, 
No. 1 1. This part of the muscle, which is termed its origin, is broad and fleshy ; its fibres incline outwards and downwards, so 
as to pass out of the pelvic cavity through the great sacro-sciatic notch, and still continuing the same direction, they become 
narrowed into a tendon, which is inserted into the posterior border of the great trochanter of the thigh-bone, or into the upper 
part of the digital fossa immediately above the gemelli. 

The two gemelli muscles are seen in fig. 1, Nos. 17, 19 ; fig. 2, Nos. 13, 15 ; and Plate XXXIII., fig. 1, Nos. 16, 18 ; these 
are small, narrow, and short muscles, which extend outwards from the ischium to the pit or fossa under the posterior margin 
of the great trochanter, enclosing between their contiguous margins part of the internal obturator muscle, fig. 1, No. 18 ; fig. 2, 
No. 14. The upper gemellus arises from the spinous process of the ischium, and the lower one from its tuberosity. As they pass 



PLATE XXXIII. 

Fig. 1. No. 1, 1. The crista of the os ilium. 2. Its anterior superior spinous process. 3. The posterior superior spinous process. 1. The 
rough part of the os ilium which gives attachment to the great gluteus muscle. 5. The sacrum. 6. The coccyx. 7. The tuberosity 
of the ischium. 8. The great sacro-sciatic ligament. 9. The small sacro-sciatic ligament. 10. The great trochanter of the thigh- 
bone. 11. The small trochanter. 12. Part of the shaft of the bone. 13. The middle gluteus muscle, (m. gluteus moditis.) 1 1. 
Its tendinous insertion into the trochanter major. 15. The pyriformis muscle. 16. The superior gemellus. 17. The obturator 
internus. 18. The inferior gemellus muscle. 19. The obturator externus muscle. 

Fig. 2. No. 1, 1. The crista of the os ilium. 2. Its anterior superior spinous process. 3. The anterior inferior spinous process. I. Tl e 
hollow of the os ilium, (fossa iliaca.) 5. The margin of the true pelvis. G, C, 6. The sacrum, its different pieces divided in the 
middle line. 7. The coccyx. 8. The great sacro-sciatic ligament. 9. The tuberosity of the ischium. 10. The internal obturator 
muscle, (m. obturator internus,) arising within the cavity of the pelvis, and passing out by the lower sacro-sciatic notch to be inserted 
into the trochanteric fossa of the thigh-bone between the two gemelli muscles ; (see fig. 1, where 17 represents the external or nfiecti <1 
part of the obturator muscle as it lies between the gemellus superior, 1G, and gemellus interior, 18.) 11. The pyriformis muscle 
arising from the sacrum within the cavity of the pelvis, out of which it passes by the great sacro-sciatic notch to be inserted into tlic 
trochanteric fossa above the gemellus superior. (In fig. 1, 15 represents the external part of the pyriformis muscle.) 12. The ct ecy« 
geus muscle. 

Fig. 3. No. 1. The crista of the ilium. 2. Its anterior superior spinous process. 3. Its concavity or fossa. 4. The transverse process of 
the last lumbar vertebra. 5. The ilio-vertebral ligament. 6. The ilio-sacral ligament. 7. The body of the os pubis. 8. The ilio- 
pectineal eminence. 9. The inner edge of the os pubis which forms its symphysis. 10. The ramus of the os pubis joining with that 
of the ischium. 11. The tuberosity of the ischium. 12. The trochanter major of the thigh-bone. 13. P*lt of the shaft of the 
thigh-bone. 14. The external obturator muscle, (m. obturator externus,) which is broad and expanded at its origin, and gradually 
narrows as it passes behind the neck of the thigh-bone to be inserted into the lower part of the trochanteric fossa. (In fig. 1, No. 19 
represents the prolonged part of the obturator externus muscle lying beneath the inferior gemellus.) 15. The quadretus i- 
muscle. 1G. Part of the anterior edge of the gluteus medius muscle. 17. Part of the gluti it i minimus n 



62 

outwards, each becomes narrow and tendinous, and at the same time contracts a more intimate connexion, or rather union, with 
the obturator muscle which lies between them, all three becoming inserted together into the fossa above indicated. 

The internal obturator muscle, (m. obturator internus,) fig. 1, No. 18; fig. 2, No. 14, is seen only in part in these drawings, 
the rest of it being concealed within the pelvis. When this cavity is laid open so as to obtain a side view of its interior, as in 
Plate XXXIII., fig. 2, No. 10, the muscle will be observed to be broad and expanded, its fibres being attached to a considerable 
extent along the side of the pelvis, for they are fixed to the inner surface of the os pubis, also to the obturator ligament, and to 
the ischium nearly as far back as the margin of the great sciatic notch. From these points they converge as they pass outwards, 
in order to issue from the pelvic cavity, through the lower or small sciatic notch. In this situation the direction of the muscle 
becomes changed, for it runs outwards and forwards, lying between the two gemelli, together with which it is inserted into the 
digital or trochanteric fossa in the upper part of the thigh-bone. This muscle acquires considerable increase of power by the 
change in its direction, for as it slides smoothly upon the border of the ischium, it moves upon a pulley-like surface, and in its 
action works with all the advantage which such a contrivance can give it. 

The square muscle, (m. quadratus femoris,) fig. 1, No. 21 ; fig. 2, No. 17, stretches outwards from the border of I he tuber 
ischii, and is inserted into the posterior margin of the great trochanter ; it is short, compressed, and flat, its form being that of an 
oblong square, and, as to its structure, it is almost all fleshy, there being but a slight admixture of tendinous fibres even at its 
attachments. 

The external obturator muscle, (m. obturator externus,) is seen only in a small part of its extent in plate XXXII. fig. l,No. 
20, fig. 2, No. 16 ; this is owing to the manner in which the muscle passes from the front of the pelvis behind the neck of the 
thigh-bone to reach its point of insertion, viz. the trochanteric fossa. By referring to plate XXXIII. fig. 3, No. 14, the position, 
form, and general direction of the muscle will be seen : it lies very deeply, being covered by all the muscles at the upper and 
inner part of the thigh ; its direction is transversely outwards, its structure fleshy in the greater part of its extent, but it ends in 
a tendon previously to its insertion, and, at its origin, there are a few aponeurotic fibres. It is broad and expanded where it is 
attached to the pelvis, its fibres being fixed to the external flat surface of the os pubis, to the rami of the os pubis and ischium, 
and to part of the ligament which fills up the obturator foramen. As the fibres incline outwards they gradually become aggre- 
gated together so as to form a thick and narrow fasciculus, which necessarily is directed behind the neck of the thigh-bone, in 
order to reach the point of insertion above indicated. 

Actions. — The six muscles included in this group conspire in their action upon the thigh-bone ; they run outwards, so that 
the direction of the fibres in most of them forms a right angle with that of the shaft of the femur ; this, together with the 
mechanical advantage given them by the length of the neck of the femur, enables them to concentrate their effort with much 
effect, so as to turn the whole limb upon its axis, and rotate it outwards. In their direction and mode of action, the muscles of 
this group bear a very close resemblance to those which are placed upon the back of the scapula, and are inserted into the great 
tuberosity of the os humeri. 



PLATE XXXIV. 

Fig. 1. No. 1. The crest of the ilium. 2. Its anterior superior spinous process. 3. The tendinous origin of the sartorius muscle, (ra. 
couturier.) 4. Its fleshy part. 5. The upper surface of the body of the os pubis. 6. Its angle. 7. The pectineus muscle. 8. The 
long adductor muscle, (m. premier adducteur.) 9. The tensor vaginae femoris muscle. 10. Its lower part, where it becomes inserted 
into the fascia lata of the thigh. 11. The anterior part of the gluteus medius muscle, (m. moyen fessier.) 12. Its tendinous insertion 
into the trochanter major. 13. Part of the gluteus maximus muscle, (m. grand fessier.) 14. Its tendon of insertion into the femur. 
15. The middle fleshy part or body of the rectus femoris muscle, (m. droit anterieur.) 10. Its tendon passing down to be inserted 
into, 17, the patella; 18. part of the vastus internus muscle; 19. the vastus externus muscle; both these are seen to unite at their 
lower part with the tendon of the rectus muscle. 20. The long head of the biceps flexor cruris muscle. 21. The short head of the 
same muscle. 22. Its tendon of insertion where it becomes fixed to the head of the fibula. 23. The external head of the gastrocne- 
mius muscle. 

Fig. 2. No. I. The external surface or dorsum of the ilium. 2. The trochanter major of the thigh-bone. 3. The tuberosity of the ischium. 
4. The great sacro-sciatic ligament. 5. The superior gemellus muscle. 6. The internal obturator muscle. 7. The inferior gemellus 
muscle. 8. The quadratus femoris muscle. 9. The insertion of the great gluteus muscle : its fibres are shown as if cut off close to 
the bone, in order that its position at this point, and its relations to the adductor magnus and the vastus externus, may be clearly seen. 
10, 10. The vastus externus muscle: the two references indicate its upper and lower part, for it extends from the base of the trochanter 
to the patella. 1 1 . The long head of the biceps flexor cruris muscle. 12, 12. The short head of the same muscle : its fibres are seen 
to project, in this view, at each side of the tendon of the long head, into which they become inserted. 13. The tendon of the biceps 
flexor muscle near its insertion into the head of the fibula. 14. The semi-tendinosus muscle. 15. Its tendon. 16, 16. The semi- 
membranosus muscle, which is broader than the preceding, and projects on each side of it. 17. The tendon of the semi-membranosus 
muscle. 18. The posterior ligament of the knee-joint. 19. The gracilis muscle, (m. droit interne.) 20. Its tendon. 21. Part of 
the sartorius muscle. 22, 22. The upper part of the adductor mao-mis muscle. 



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63 

On reviewing the muscles exhibited in these drawings, it will at once be observed how many provisions there are for turning 
the thigh outwards. The psoas and iliacus muscles, which we have exhibited in a former number, are also to a certain extent 
rotators ; and even the adductors of the thigh can turn the femur somewhat on its axis, and incline it outwards. Now, when so 
many moving powers conspire to produce such a result as this, it will be asked what are their opponents ? We find that the 
antagonizing powers are few, and comparatively feeble. The tensor vaginae femoris is enabled, by its peculiar direction and 
mode of connexion with the fascia lata, to act upon the thigh, and rotate it inwards, and the anterior fibres of the gluteus medius 
muscle assist in producing the like result by reason of their oblique direction, and their insertion into the great trochanter. These 
are the only antagonists to the external rotator muscles, and accordingly we find that the power of turning the limb inwards is 
comparatively feeble, and that the effort is made with something of restraint, if not with awkwardness. 



PLATE XXXIII. 

The muscles exhibited in this plate have been already described with the two groups above noticed, viz. the glutei, and the 
external rotators ; their names are given in the references at the foot of the page. One muscle, however, is here shown, which 
does not belong to either set, as it forms part of the deep perinaeal, which we shall have to notice in a subsequent number: it is 
the coccygeus, fig. 2, No. 12 ; it may be called ischio-coccygeus, so as to make its name express the points to which it is attached. 
It is a flat triangular muscle placed at the outlet of the pelvic cavity at its outer and back part, which it assists in some degree to 
close, by being stretched from the spinous process of the ischium to the side of the coccyx and the contiguous part of the edge 
of the sacrum ; it is composed of tendinous and fleshy fibres, and is so placed that its inner surface supports the rectum, and the 
external one is covered by the lesser sacro-sciatic ligament. 

Dislocations of the Hip-joint. — We can scarcely dwell for any length of time upon the lines of direction of the different 
muscles round a joint, and their points of attachment to the bones which form it, without making an endeavour to determine 
what their several and combined actions are in the natural condition of the parts ; and when we have made this step, and have 
fixed in our mind an accurate conception of the powers and influences of the muscles, we are insensibly led to inquire what is 
their state and condition when one of the bones is displaced. It is obvious that the muscles under such circumstances are thrown 
into a new relation with regard to the joint ; — the line of direction of some is changed ; the fibres of one set are put upon the 
stretch in consequence of their points of attachment being farther apart in the new position of the bones than previously ; and 
this may be carried so far in particular instances, that laceration of the muscular structure, or of the tendons, may be produced. 
In other cases, on the contrary, the muscular fibres are relaxed, owing to their points of attachment being approximated. These 
various conditions of the muscles influence the state of the limb, and determine its line of direction, as well as the aspect and 
outline which the neighbouring region of the joint presents ; hence the phenomena of dislocations form a proper sequel to the 
study of the actions of muscles, more particularly as they are the opponents which resist our efforts to restore the bones to their 
natural position. 

Dislocation of the thigh-bone is not by any means so frequent as that of the humerus. It may take place in either of four 
directions ; the most frequent form of the accident is that in which the head of the bone is thrown upwards and backwards on 
the dorsum of the os ilii ; the next is that in which it is thrown downwards and inwards on the foramen ovale ; the third is that 
in which it passes backwards into the ischiatic notch ; and the fourth where it rests upon the body of the os pubis. Were we to 
endeavour to determine the relative frequency of these displacements by A priori considerations founded on the structure of the 
joint, and not by appealing to the results of experience, or were it left to a mere anatomist to determine the question, he would 
be very likely to say that the dislocation into the foramen ovale must be more frequent than that upon the dorsum ilii, for the 
margin of the articular cavity at its upper and outer part is more prominent than at the lower and inner, — the capsular ligament 
is thick and strong in the former situation, and comparatively thin and weak in the latter ; added to this, the movement of abduc- 
tion may be carried to a very considerable extent, which will make the head of the bone glide downwards and inwards, where 
the least resistance is opposed to it; yet, of twenty cases, the results of which have been noticed in Guy's Hospital, twelve 
presented the first form of dislocation, five that into the foramen ovale, three that on the os pubis, and one into the ischiatic 

Kptch. 

When the bone is thrown backwards upon the dorsum ilii, the state of the limb is as follows : it is rendered shorter than its 
fellow by about two inches, so that the great toe rests upon the tarsus of the other foot : the foot and the leg are turned inwards, 
and the knee somewhat advanced before the opposite one : the hip loses its roundness and fulness, the nates appearing somewhat 
flattened when compared with that of the sound side ; and the trochanter major is thrown upwards so as to be brought nearer 
the anterior superior spinous process of the ilium; the foot cannot be turned outwards without causing much pain, but its incli- 
nation inwards may be increased. The limb will not admit of being abducted, but it may be drawn slightly across that of the 



64 

other side. It is usually said that this accident may be confounded with fracture of the neck of the thigh-bone, but these acci- 
dents have but one circumstance in common, viz. the shortening of the limb. In the fracture just named, the knee and foot are 
turned outwards ; the thigh may be raised up somewhat towards the abdomen, although the attempt to effect this causes pain ; 
and lastly, by a slight degree of extension, the length of the limb can be restored to its usual length, but it will become shortened 
again when the extension is discontinued. 

When we refer to the reports of cases* of dislocation on the dorsum ilii, we find that this accident may occur under various 
circumstances. A man who worked as a labourer in a deep clay-pit "was in the act of stooping, with his left knee bent behind 
the other," when a large mass of clay fell upon him, so as to bury him in the earth. When removed from this position, the 
thigh-bone was found to be thrown upon the ilium. In another case, the displacement was occasioned " by a cart passing over 
the pelvis." A robust man " fell from a height of about four feet, and dislocated his hip." A carter, " in springing from the 
shaft of a wagon, slipped, and had his hip driven against the wheel with considerable force." The wheel of a cart "passed 
between a man's legs and over the upper part of the thigh, and produced dislocation on the dorsum ilii ;" and the same accident 
occurred to a child, who, " whilst swinging on the shaft of a cart, which, being insecurely propped, suddenly gave way, and she 
fell to the ground upon her side." These different statements, taken from Sir A. Cooper's work on dislocations, merely make us 
acquainted with the circumstances under which the accident has occurred, and therefore might occur again, but do not furnish us 
Avith any adequate data from which we may infer how it is produced. It is not easy to perceive what they have in common, or 
why the same identical result should follow from accidents so various in their degree and character. Still, however vague and 
indeterminate they may be, they are of importance, inasmuch as they are taken from authentic reports of cases treated by 
competent persons. The following passage from Boyert will show the risks which even the best-informed men incur of falling 
into error when they venture to decide upon subjects of this sort by d. priori considerations. " When by a fall, from a place 
more or less elevated, on the soles of the feet, or on the knees, the thigh is pushed forwards and inwards, the head of the femur, 
forced towards the superior and external part of the acetabulum, breaks the internal and orbicular ligaments, escapes through a 
laceration in the latter, and ascends on the external face of the os ilium; but as the part of the os ilium immediately above and 
at the external side of the cavity is very convex, the head of the femur soon abandons its first position, and slides backwards and 
upwards into the external fossa of the os ilium, following the inclination of the plane towards the fossa, and obeying the action of 
the glutei muscles, which draw it in this direction. The head of the femur, in ascending thus on the external face of the os ilium, 
pushes upwards the gluteus minimus, which forms a sort of cap for it; and the gluteus maximus and medius are relaxed by the 
approximation of the points into which they are inserted. The pyriformis is nearly in its natural state; the gemini, obturatores, 
and quadratus femoris, are a little elongated. The psoas magnus and iliacus internus are relaxed, as are also the other muscles 
inserted into the trochanter minor. If to this description it be added that the orbicular ligament, torn at its superior part, is stretched 
over the acetabulum and covers it, an exact idea may be formed of the changes occasioned in the surrounding parts by this 
luxation of the femur." 

The statement here given in the words of M. Boyer, has evidently been drawn up, not from any case of dislocation which 
this distinguished surgeon had observed himself, or from any " post mortem" examination which he had ever conducted. We 
cannot find any case in which luxation of the thigh-bone backwards and upwards was produced by a fall on the soles of the feet 
or on the knees, yet from the passage above cited it would appear to be the most ordinary cause of the accident; and the condition 
of the muscles round the joint appears to be indicated from anatomical considerations, and not founded on observation. In the 
third volume of the Dublin Hospital Reports a case is detailed at considerable length by Mr. Todd, which places in a clear point 
of view the condition of the different textures about the hip-joint in this form of dislocation. The nature of the accident was 
ascertained soon after its occurrence, and the efforts to effect the reduction of the dislocation were successful; but the patient died 
from the injuries which he had previously sustained. When proceeding with the dissection, Mr. Todd found, " after he had 
raised the gluteus maximus, a cavity filled with coagulated blood between it and the posterior part of the gluteus medius;" this 
obviously marked the position which the head of the bone had occupied; the glutei muscles were uninjured, but "the rotators, 
together with the pyriformis, were torn across." Some fibres of the pectineus also were torn; the capsular ligament of the joint 
remained entire at its upper and fore part, but was torn in all the rest of its extent. The round ligament was broken off near the 
head of the femur. Thus the condition of the muscles was found to be very different from that which Boyer had indicated. It 
is to be regretted that the report does not expressly say what was the state of the psoas and iliacus muscles: Boyer had inferred 
that they were relaxed as well as "the other muscles inserted into the trochanter minor," by which latter clause he doubtless 
alludes to the pectineus, which is inserted a little beneath it. But this muscle appears to have been stretched, so that "some of 
its fibres were even torn;" and such, we make no doubt, was the condition of the psoas and iliacus, both at the moment in which 
the head of the bone was sliding over the brim of the acetabulum, and even subsequently, when it rested upon the dorsum ilii; 
for the trochanter minor, though raised above its natural position, is carried so far back that the distance between the point of 

* A Treatise on Dislocation and Fractures, by Sir Astley Cooper, p. 41, et seq. 
f Lectures on Diseases of the Bones, vol. ii. p. 158. 



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insertion of the muscles, and the brim of the pelvis over which they slide, is greater in the new position of the limb than in 
its natural state ; in other words, these two muscles as well as the pectineus are in a state of tension, and to this is owing the 
position in which the injured limb is found, viz. that it is drawn forwards and inwards, and in advance of that of the opposite 
side. Moreover, the mode in which the extension is made by all surgeons has reference to the condition of the psoas and iliacus 
muscles, for the limb is drawn, at least when the extension is being commenced, in that direction which is most likely to relax 
them. 

It has often been asked how it comes to pass that the foot and limb are turned inwards in this form of dislocation. Boyer 
inclines to the opinion, that it depends on the external portion of the capsular ligament, which comes from the anterior inferior 
spine of the ilium; this portion, which is very thick, being stretched in the luxation upwards, draws the great trochanter forwards, 
and thereby turns the entire limb inwards. He had previously laid down the general principle, that the position of limbs when 
luxated is always "determined by the elongation of the muscles of the side opposite to that to which the luxated bone is carried ;' ; 
— for instance, in the luxation of the arm downwards into the axilla, the deltoid and supra-spinatus muscles, being stretched by 
the separation of their points of attachment, give the arm an oblique direction, and cause the elbow to project outwards from 
the side. If he had followed up this view of the case, he would have concluded that the trochanter was drawn forwards, at the 
moment in which the head of the bone is slipping over the brim of the acetabulum, by the contractile effort of the anterior fibres 
of the gluteus medius, which are then put on the stretch, and that they are aided in this by the tensor vaginae femoris. But the 
influence of these two muscles he overlooked, and dwelt on the power of the short external rotators, which he supposed to remain 
entire, and still to possess their ordinary power over the limb, were they not controlled by some superior agency. His words are, 
"the obturatores, gemini, and quadratus femoris, being elongated, the point of the foot ought to be turned outwards:" but finding 
in all cases the reverse to be the fact, he comes to the conclusion that the power of the muscles is contravened by the ilio-femoral 
ligament. Sir Astley Cooper gives a different explanation of the position of the limb ; he says it may be caused " by a fall when 
the knee and foot of the patient are turned inwards, or by a blow whilst the limb is in that position, and the head of the bone is 
thus displaced upwards and turned backwards." It is difficult to conceive how the head of the bone could quit its articular 
cavity whilst the limb is in the extended position, so as to be forced upwards, unless the brim of the acetabulum were at the same 
time broken. It may be forced backwards by a sudden and violent blow given to the posterior edge of the trochanter when a 
person is unprepared for any such occurrence ; for, under these circumstances, the head of the bone is made to glide backwards 
to the posterior lip of the acetabulum, and to press so forcibly against the capsular ligament as to tear through it and escape from 
the articulation. We can readily perceive that this luxation may be produced by a force applied to the outer side of the knee 

PLATE XXXV. 

Fig. 1. No. 1. The sacrum, divided along the middle line. 9. The coccyx. 3. The os pubis; the line of its symphysis. 4. Its ramus. 
5. The tuberosity and ramus of the ischium. 6. The internal obturator muscle, as seen within the pelvis, from which it passes out 
through the small sacro-sciatic notch; its external portion is shown in several of the preceding plates; for instance, in plate XXXIV. 
fig. 2, No. G. 7. The origin of the pyriformis muscle from the anterior surface of the sacrum. 8. The gracilis muscle lying along the 
inner side of the thigh, and ending in a tendon, 9, which is prolonged to the tibia. 10. The semi-tendinosus muscle. II. Its tendon. 

12. The semi-membranosus muscle. 13. The biceps flexor cruris muscle. 14. Its tendon passing to its insertion into the head of the 
fibula. 15. The lower part of the sartorius muscle. 16. Part of the vastus internus muscle. 17. A small portion of the rectus 
femoris muscle. 18. The adductor magnus muscle, which is seen to be attached above to the tuberosity and ramus of the ischium. 19. 
A small part of the same muscle which is fixed higher up to the ramus of the os pubis. 20. A small portion of the adductor brevis 
muscle. 21. The upper part of the adductor longus muscle, where it descends from its attachment to the angle of the os pubis. 22. 
The patella. 23. The popliteal space, being the deep interstice between the flexor or ham-string muscles. 21. The upper part of the 
gastrocnemius muscle. 

Fig. 2. No. 1. The outer head or tuberosity of the tibia. 2. The upper head of the fibula. 3. The anterior tubercle of the tibia. 4. The 
lower extremity of the fibula, forming the external ankle. 5. The posterior part of the os calcis. G. The fifth metatarsal bone. 7. 
The tibialis anticus muscle. 8. Its tendon passing down under the annular ligament. 9. Part of the tendon of the extensor proprins 
pollicis muscle, as seen in the interstice between the tibialis anticus and the common extensor muscle. 10. The tendon of the extensor 
pollicis, where it rests on the dorsum of the foot, after having passed under the anterior annular ligament. 11. The upper fleshy portion 
of the common extensor muscle of the toes. 12. Its tendon passing down to the ankle and under the annular ligament 13, 13, 13, 

13. The four tendons which are given off by the common tendon, and proceed over the foot to the four !> ss< it toes. 1 1. The peronens 
tertius muscle. 15. Its tendinous insertion into the fifth metatarsal bone. 1G. The fleshy part of the peroneus longus muscle. 17. 
Its tendinous attachment to the head of the fibula. 18. Its tendon passing down behind the external ankle 19. The same tendon, 
wnere it runs upon the outer side of the os calcis, and passes into the sole of the foot. 20, 20. The peroneus brevis muscle; the two 
references indicate that its fibres project on each side of the tendon of the peroneus longus. 21. The tendon >>f the peroneus brevis 
passing to its insertion into the posterior extremity of the fifth metatarsal bone. 2-2. Thei Bvis digitorum muscle, 23. -J.'t, 
23, 23. The four tendons which it gives off to the four inner toes. 21. The upper fleshy part of the gastrocnemius muscle. -J.">. The 
outer border of the soleus muscle. The fleshy fibres of this muscle and of the gastrocnemius are seen passing with \ 

obliquity to be inserted into the tendo Achillis, 2G ; and this descends to be fixed to the posterior extremity of the os calcis. 

Muscles. — 9 



66 

when the limh is in the semi-flexed position, for then the head of the bone, sliding backwards and upwards in the acetabulum, is 
forced against the capsular ligament and ruptures it. In this state the rotators have little power, for the line of direction of most 
of them nearly coincides with that of the femur; and this is the position in which the anterior fibres of the gluteus medius and the 
tensor vaginae can act upon the trochanter major, and draw it forwards, thereby placing the head of the bone in the position 
which it is known to assume in the dislocation on the dorsum ilii. 

Dislocation into the foramen ovale. — The head of the thigh-bone is in some cases displaced in the opposite direction from 
that which we have above stated, and thrown downwards into the situation of the foramen ovale. Were we to judge solely 
from the anatomical conformation of the joint and the movements of the limb, we should be disposed to conclude that this 
displacement would occur more frequently than that on the dorsum of the ilium ; for the capsular ligament is weaker at the lower 
and inner part of its extent than elsewhere, and the round ligament, by reason of its attachment to the margins of the cotyloid 
notch, does not check the descent of the bone towards the foramen ovale : Boyer goes so far as to say that the rupture of the 
round ligament is not a necessary consequence of this form of dislocation ; upon which point, however, he is at issue with Sir 
Astley Cooper, who states that " the ligamentum teres, as well as the lower and inner part of the capsular ligament, is torn 
through ;" — finally, this form of accident is in a manner facilitated by the great extent to which the thigh may be abducted. 
Notwithstanding all these circumstances, the dislocation on the dorsum of the ilium is found to be of more frequent occurrence. 
The head of the bone cannot be thrown downwards and inwards unless when the thigh is in a state of forcible abduction, a 
position in which the limb is placed in many accidents to which persons are liable. When this displacement occurs, the limb is 
found to be about two inches longer than the other, the trochanter major is less prominent, the knee is carried forwards and 
separated from the other, so as not to admit of being brought into contact with it, or approximated to the axis of the body without 
great difficulty. In the standing posture the body is bent forwards ; the foot, though widely separated from the other, is stated 
by Sir Astley Cooper to be turned neither outwards nor inwards ; in his plate it is figured as if the toe were directed forwards, 
but he does not consider that the direction of the foot affords any diagnostic mark of the accident, as he found it to vary somewhat 
in different instances. The increased length of the limb, the separated knees, the bent position of the body, all point to the nature 



PLATE XXXVI. 

Fig. 1. The muscles of the leg are here shown as they are seen at its outer side when the skin and the fascia are removed. 

No. 1. The patella. 2. The upper extremity of the tibia. 3. The external ankle, formed by the lower extremity of the fibula. 4. The 
posterior extremity of the fifth metatarsal bone. 5. The os calcis. 6. Part of the tendon of the rectus femoris muscle, where it descends 
to its insertion into the patella. 7. Part of the vastus externus muscle. 8. The biceps flexor muscle. 9. The upper extremity, or 
origin, of the long peroneus muscle. 10. The fleshy part of the same muscle. 11, 11. Its tendon passing down behind the external 
malleolus, and upon the outer side of the os calcis, from which it is prolonged into the sole of the foot, after having turned round its 
outer border. 12, 12. The fleshy part of the peroneus brevis muscle; its fibres are seen projecting beyond the tendon of the 
peroneus longus. 12.* The tendon of the peroneus brevis passing to its insertion into the fifth metatarsal bone. 13. The external 
head of the gastrocnemius muscle. 1 4. Its tendon, — tendo Achillis. 1 5. The lower part of the same tendon descending to its insertion 
into the os calcis. 16. The soleus muscle; its fibres are seen descending obliquely backwards to be inserted into the tendo Achillis. 
17. The fleshy part of the tibialis amicus muscle. 18. Its tendon passing down towards the ankle. 19. The same tendon where it 
inclines towards the inner border of the foot: its position previously to its insertion is shown in fig. 2, No. 19. 20. The extensor 
communis digitorum muscle. 21. The tendon in which its fleshy fibres end. 22, 22, 22, 22. The digital processes into which this 
tendon divides, and which are prolonged over the dorsum of the foot to the four smaller toes. 23. The peroneus tertius muscle. 24. 
Its tendon at its insertion into the fifth metatarsal bone. 25. The tendon of the extensor muscle of the great toe (m. extensor pollicis 
longus,) appearing in the interstice between the tendons of the tibialis anticus and extensor communis digitorum : from this point it will 
be observed to descend in front of the ankle-joint, and from thence over the dorsum of the foot to the great toe. 26. The extensor brevis 
digitorum muscle ; on the dorsum of the foot. 

Fig. 2. The muscles of the leg and foot, as seen at the inner side, after the skin and fascia have been removed. 

No. 1. The patella. 2. The front of the tibia. 3. The anterior annular ligament of the ankle-joint. 4. The articulation of the base of 
the first metatarsal bone. 5. The os calcis. 6. The tendon of the rectus muscle, close to its insertion into the patella. 7. 
A few fibres of the vastus internus muscle. 8. The sartorius muscle, as it passes by the inner side of the knee-joint. 9. The expanded 
aponeurosis in which this muscle terminates previously to its insertion into the tibia, and which will be observed to conceal the tendons 
of the gracilis and semi-tendinosus muscles. 10. The tendon of the gracilis muscle. 11. Part of the semi-membranosus muscle. 
12. The semi-tendinosns muscle. 13. The inner head of the gastrocnemius muscle. 14. The upper broad part of the tendo Achillis, 
in which the fibres of the gastrocnemius and of the soleus terminate. 15. The lower part of the tendo Achillis, near its insertion into 
the os calcis. 16. The inner edge of the soleus muscle; its fibres are seen inclining obliquely backwards as they descend to be 
inserted into the tendo Achillis. 17. A few fibres of the anterior edge of the tibialis anticus muscle. 18. Its tendon, as it descends 
obliquely inwards. 19. The same tendon turning to reach the inner border of the foot, beneath which it is inserted into the internal 
cuneiform and first metatarsal bone. 20. The tendon of the flexor communis digitorum muscle; 21. the tendon of the tibialis posticus 
muscle:— these are observed passing down behind the internal ankle in order to reach the sole of the foot. 22. Part of the tendon 
of the flexor longus pollicis, which in this view can be but slightly seen. 23. The origin of the adductor pollicis muscle. 24. The 
tendon in which its fleshy fibres terminate. 25, 25. Two of the tendons of the extensor communis digitorum muscle. 



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67 

of the accident ; and if at the same time a hollow is perceived beneath Poupart's ligament, and the head of the bone be felt a little 
before and beneath the axis of the acetabulum, no doubt will remain as to the form of the dislocation. In a case of this sort, 
which Sir Astley Cooper had an opportunity of examining after death, he found the head of the thigh-bone lodged in the foramen 
ovale, the obturator externus muscle being entirely absorbed. The accident was evidently one of long standing, as the foramen 
ovale was filled up by bone, and osseous matter was deposited round its margin, so as to form a new socket for the head of the 
femur. The original acetabulum was nearly filled up with bony matter, the round ligament was torn through, and also the 
capsular ligament in part of its extent ; the pectinalis muscle and the adductor brevis had been lacerated, but were united by 
tendinous fibres ; the psoas and iliacus muscles, the glutei and the pyriformis, were all stretched. Sir Astley does not, however, 
say in what condition he found the gemelli and obturator internus muscles, or the quadratus femoris ; but if the pyriformis is stretched, 
these must be much more so, and most likely are torn across at the moment that this accident occurs ; and as the adductor brevis 
was found to have been torn, it is sufficiently obvious that the adductor longus and magnus must be elongated and stretched, in 
which condition they can readily be felt along the inner side of the thigh, forming a tense margin. This condition of the muscles 
necessarily tends to evert the toes, the only countervailing agent being the tensor vaginae femoris, and perhaps a few fibres of the 
gluteus medius ; hence, though in the general summary of the symptoms Sir Astley Cooper states that the toes are neither turned 
inwards nor outwards, in the first case, the history of which he details, page 60, " the toes were rather everted," and in the second 
case, page 62, "the foot was rather inclined outwards." When this dislocation remains unreduced, the limb is too long, and 
occasions a halt and a lameness, so that in progression the elongated extremity would be made to describe a curve outwards at 
each step which is taken. 

In recent cases, the reduction of this dislocation is in general easily effected. Sir Astley Cooper directs the patient to be 
placed upon his back with his thighs separated as widely as possible ; that a girth be passed round the flexure of the luxated 
thigh, and fixed to a staple in the wall or in the bedpost ; the surgeon then takes hold of the ankle of the dislocated side, and 
draws it steadily inwards in front of the sound limb, by which means the head of the bone will be dislodged from its new position 
and forced backwards towards the acetabulum, into which it will pass with a jerk or snap, caused by the action of the muscles 
which were put on the stretch during the unnatural position of the limb. Whenever the dislocation has remained unreduced for 
two or three weeks, it is found necessary to place the patient in a different position in order to effect the reduction. He should 
be placed upon the sound side. The pelvis is then fixed by a bandage carried round it, and counter-extension is to be effected 
by a girth carried round the dislocated thigh, and fixed to a pulley suspended over the patient. Extension is then made by 
drawing the dislocated thigh directly upwards, the knee and the foot being pressed down so as to prevent the lower part of the 
limb from being elevated with the thigh-bone. In this way the thigh is made a lever of considerable force, by means of which 
the efforts of extension are directed upon the muscles which oppose the reduction, so as to overcome their resistance. 

Dislocation backward into the ischiatic notch. — When the head of the femur is thrown backwards out of the acetabulum, it 
rests upon the pyriformis muscle, and occupies the interval between the small sacro-sciatic ligament and the margin of the ischiatic 
notch. This accident may be either primary or secondary ; that is, it may be the direct and immediate result of force or violence 
so applied to the limb as to throw the bone from its articular cavity into the position here indicated, or it may follow and be a 
consequence of another mode of dislocation ; not, however, in the manner in which Boyer* states it, for he seems to think that the 
head of the femur, in a case of luxation upwards and outwards, may slide from the position which it at first occupies upon the 
external surface of the ilium downwards and backwards into the ischiatic notch, its passage in this direction being favoured by 
the bending of the thigh upon the pelvis. This mode of explaining the occurrence proceeds on the assumption that a second 
disturbing force is applied to the limb immediately after the dislocation on the dorsum ilii had occurred, somewhat in the same 
way as dislocation of the os humeri forwards under the pectoral muscle is made to supervene upon a primary displacement of the 
bone downwards into the axilla. It very seldom, if ever, happens that a second injury follows so quickly upon the first as to 
produce a secondary displacement of the femur in this way ; but it may readily occur during the effort to reduce a primary 
dislocation upon the dorsum ilii, if the extension of the limb be discontinued before the head of the bone is drawn downwards 
to a level with the acetabulum ; for if it be let go too soon, the muscles will draw it directly backwards into the ischiatic notch: 
this I have known to occur in one instance, and the secondary luxation was never reduced. It may also occur as a consequence 
of dislocation into the foramen ovale ; for if the thigh is large and fleshy, it must necessarily incline somewhat forward during 
the effort to effect its reduction by drawing it across the sound limb, and so some risk is incurred of tilting the head of the bone 
backwards beneath the acetabulum into the ischiatic notch. To prevent the possibility of such an occurrence, Mr. Key, in a case, 
the particulars of which he transmitted to Sir Astley Cooper, (on Dislocations, p. 67,) " thought it advisable to carry the leg 

behind the sound one." 

In the dislocation now under notice the limb is somewhat shortened, usually however not more than hall an inch or an inch. 
The ere-it toe rests against the inner side of that of the other foot; the knee and the foot are slightly turned inwards, the inclina- 
t' " that direction being less than in the dislocation on the dorsum ilii; neither is the knee so much in advance of the sound 

* Lectures on Diseases of the Bones, vol. ii. p. 167. 



68 

limb as in the last-named accident. When the patient is in the standing posture, the toe, but not the heel, will touch the ground. 
On feeling for the trochanter major, it will be found behind its usual position, and having a very slight inclination towards the 
acetabulum ; but the head of the bone is sunk so deeply into the ischiatic notch that it can scarcely be felt except in very thin 
persons. 

Boyer appears to have formed his opinion as to the condition of the limb in this accident from merely anatomical considera- 
tions, and not from observation of cases which presented themselves to his notice. He says that when this luxation is primary, 
the limb is lengthened, the great trochanter by descending is removed farther from the spine of the ilium, and that the knee and 
foot are turned " outwards ;" but if it be secondary, the knee and loot are turned " inwards." Sir Astley Cooper observes, that 
this error as to the state of the limb runs through the writings of every author who has treated of the subject, and he proceeds 
to point out the mistakes in practice to which such a description may give rise when it is unreservedly adopted. A gentleman 
wrote to him from the country to say that he had under his care a case of injury of the hip, which he would suppose to be a 
dislocation into the ischiatic notch, but that the limb was " shorter instead of being longer, as authors state it to be." 

The circumstances under which this dislocation occurs are various. Thus, one person, whilst carrying a bag of sand, 
" stepped unexpectedly into a hollow in the road on which he walked, when his knee was turned inwards, at the same time that 
his body fell forwards with some violence." Another person, a sailor, rested his foot upon a chest raised a little way from the 
ground, when a box or basket fell upon his thigh, " striking the knee inwards." He fell ; and when brought for examination, it 
was found that the head of the thigh-bone was thrown backwards into the ischiatic notch. In this latter case, the knee appears 
to have been pressed inwards whilst the thigh was placed at right angles with the abdomen ; this position of the limb appears to 
be necessary to the production of the accident. 

The reduction of this dislocation is confessed by all persons to be difficult, in consequence of the peculiar situation of the 
head of the bone with regard to the acetabulum ; for it must be drawn towards the articular cavity, and also lifted over its margin. 
'The patient is to be laid upon a table, resting on the sound side, and a girth placed between the pudendum and the inner part of 
the thigh, so as to fix the pelvis, and this is attached to a ring fixed behind the line of direction of the body ; a wetted roller and 
strap should then be applied above the knee ; to this a pulley is attached, which is fixed before the line of the body. The 
adjustment being thus made, the dislocated femur is drawn obliquely downwards across the other thigh; and whilst the extension 
is steadily kept up, an assistant passes a napkin under the upper part of the thigh, with which he lifts the bone as it is drawn 
towards the acetabulum over its brim. It is also found necessary to rotate the limb inwards, in order to facilitate the passage of 
the head of the bone over the margin of the articular cavity. As to the condition of the parts around the articulation, we are 
informed by Sir Astley Cooper that, in a case which he met with accidentally in the dissecting-room, and in which the luxation 
was not reduced, the original acetabulum was filled with a ligamentous substance ; the capsular ligament was torn at its 
anterior and posterior part, but not at the superior and inferior ; the round ligament was broken across, a part of it still remaining 
adherent to the head of the bone ; the head of the femur, placed behind the acetabulum, rested upon the pyriformis, which 
muscle was diminished, but still there was no bony socket formed for the head of the bone : a new capsular ligament, however, 
was established, apparently consisting of condensed cellular membrane. It is to be regretted that all mention of the state of the 
muscles has been omitted in this report, more particularly as Boyer appears to have indicated their condition from anatomical or 

PLATE XXXVII. 

Fig. 1. The superficial muscles of the calf of the leg are here shown as they are viewed from behind. 

No. 1. The lower part of the thigh-bone. 2. Its inner condyle. 3. The outer condyle. 4, 4. The two heads of the gastrocnemius 
muscle. 5, 5. The broad fleshy part of the same muscle, where it forms the thick part of the calf of the leg. 6. The tendo Achillis, 
in which the fibres of the gastrocnemius muscle are inserted, and which is prolonged downwards to the os calcis. 7, 7. Some of the 
lower fibres of the soleus muscle, projecting on each side of the preceding muscle, and descending with an inclination backwards to be 
inserted into the anterior surface of the tendo Achillis. 8. The tendon of the tibialis posticus muscle, where it passes behind the 
inner ankle. 9. The tendon of the flexor communis digitorum muscle. 10. The tendon of the flexor pollicis longus muscle. 11. 
The peroneus longus muscle ; its posterior border. 12. Its tendon passing behind the external ankle. 13. Part of the peroneus brevis 
muscle. 14. Its tendon. 15. Part of the fibrous band which binds down these tendons. 16. The cellular and adipose substance 
which forms the cushion of the heel, cut through. 17. The tegument covering the inner border of the foot. 18. The tegument 
at the outer border of the foot. 

Fig. 2. No. 1. The lower part of the thigh-bone. 2. Its inner condyle. 3. The outer condyle. 4. The fleshy part of the plantaris muscle. 
5. Its long thin tendon. 6. Part of the popliteus muscle. 7, 7. The broad fleshy portion of the soleus muscle. 8. The upper part 
of the tendo Achillis ; this tendon will be observed to be cut across at its point of junction with the gastrocnemius, which muscle is 
altogether removed, in order to bring the soleus and plantaris into view. 9. The os calcis, giving insertion to the tendo Achillis. 10. 
The tendon of the tibialis posticus muscle. 1 1. The flexor communis digitorum muscle. 12. The tendon of the flexor longus pollicis 
muscle. 13. The posterior edge of the peroneus longus muscle. 14. Its tendon descending behind the external ankle. 15. Part of 
the peroneus brevis muscle. 16. Its tendon. 17. A few fibres of the flexor longus pollicis muscle. 18. The subcutaneous cellular 
and adipose substance which was cut through while making the dissection. 



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69 

a priori views. He tells us that the muscles which cover the posterior part of the acetabulum, such as the pyriformis, gemelli, 
obturatores, and quadratus femoris, are raised up and stretched; and that the psoas magnus and iliacus are in a great state of 
tension, which explains the turning of the limb " outwards." In all the cases of which we have detailed statements, the foot is 
stated to have been turned "inwards ;" and as to the condition of the rotator muscles, they are much more likely to be torn than 
merely ; < raised up and stretched." 

Dislocation forwards on the pubes. — The head of the thigh-bone may be protruded from the acetabulum, and made to pass 
forwards towards the pubes, so as to rest upon the brim of the pelvis. When this has happened, the dislocated limb becomes 
shorter than the other by about an inch ; the knee and foot are turned outwards, and cannot be rotated inwards ; the great 
trochanter is approximated somewhat to the anterior superior spinous process of the ilium, and lies a little before it ; the head of 
the bone, like a hard round ball, can be distinctly perceived to project above the level of Poupart's ligament, supported on the 
brim of the pelvis, lying to the outer side of the femoral vessels. Though this accident appears easy of detection, Sir A. Cooper 
met w'ith three instances in which it was altogether overlooked, until it was too late to admit of being reduced. In a case of this 
kind, which was dissected after death, the capsular ligament was found to be extensively lacerated, and the round ligament broken 
through ; the head of the thigh-bone had raised up Poupart's ligament, having slipped between it and the os pubis. In this 
position the tendon of the psoas and iliacus muscles was raised up and passed over the neck of the bone as they descended to 
their insertion. The crural nerve, lying between the iliacus and psoas, passed in front of the neck of the bone. The original 
acetabulum had become partly filled up by osseous deposit, and was greatly altered in form ; so was the trochanter major, which 
lay upon it. A new articular cavity was formed upon the os pubis, which supported the neck of the bone, for its head projected 
above the brim of the pelvis. Poupart's ligament lay before the head of the bone ; the femoral vessels to its inner side, and the 
anterior and inferior spinous process to its outer side. 

This accident occurs in various ways. Sir A. Cooper gives the report of a case communicated to him by Mr. Tyrrell, in 
which this dislocation was produced by violence applied directly to the part. " A man, whilst standing at the corner of a street, 
was struck on the back part of the right hip by a cart-wheel, and knocked down by the blow." In this instance the head of the 
bone could be distinctly felt under Poupart's ligament, immediately to the outside of the femoral vessels. The limb was turned 
outwards, but was very little altered in its length ; it could be rotated outwards, but not at all inwards, the thigh admitting 
only of a partial abduction and adduction. In a case which presented itself to Desault, the accident occurred in a very different 
way : the subject of it was a porter in one of the markets. This man's foot happened to slip whilst a heavy burden was being 
placed upon his shoulder: his leg and thigh were carried backwards, his body also became inclined a little backwards; and in 
the struggle to recover the erect position, the head of the femur was thrust forwards and upwards, so as to tear through its cap- 
sular ligament, and pass forwards into the fold of the groin, where it was distinctly perceptible. 

When proceeding to effect the reduction of this dislocation, the patient is placed on a table, resting on the sound side, and 
a girth is passed between the pudendum and inner part of the thigh, and fixed to a staple placed a little before the line of the 
body ; a roller and strap are then bound a little above the knee, in the usual way, to which a pulley is attached, in order to make 
extension. The traction should be made in such a way that the thigh-bone is drawn in the direction of a line a little behind that 
of the axis of the body. When extension is kept up for a short time, another bandage is to be applied around the upper part of 
the thigh, close to the perinaeum, by means of which the head of the bone is raised. In this manner the reduction is accom- 
plished without much difficulty in recent cases. 

What, it will be asked, is the relative frequency of these different modes of dislocation of the thigh-bone ? Sir A. Cooper 
gives, as the result of his extensive observation, the proportion in this way : out of twenty cases, he found twelve on the dorsum 
ilii, five in the ischiatic notch, two in the foramen ovale, one on the pubes. 



PLATE XXXI. 

The muscles placed at the fore part of the thigh are exhibited in these drawings ; the skin, the fascia, and the vessels being 
all removed. 

The Tensor muscle. — At the upper and outer part of the limb a short muscle is seen, marked 5, 6, extending obliquely 
downwards from the point of the hip, and terminating a little below the prominence (trochanter major) of the thigh bone. This 
is the tensor muscle of the fascia of the thigh, (m. tensor vaginas femoris.) It is compressed and flat in the greater part of its 
extent narrow at its upper extremity, but becomes wider towards the lower. It arises from the anterior superior spinous process 
of the ilium where it is fixed to the outer surface of the bone by tendinous fibres; to these the muscular fibres succeed, and spread 
out somewhat as they run downwards, and terminate by becoming inserted between two layers of the fascia lata of the thigh, 
which in a manner embrace them. The inner or anterior edge of the muscle is observed to be in apposition for a while with the 



70 

■arteritis muscle, (No. 8,) but lower down an interval is left between them by their divergence, in which the rectus, No. 10, (which 
at its upper part is concealed by them,) comes forward into view. 

The Sartorius muscle.— Along the anterior and inner aspect of the limb a lengthened strap-like muscle is seen to lie extended 
from the most prominent point of the hip, downwards and inwards, across the muscles of the thigh ; then changing its direction, 
so as to descend by the inner side of the knee-joint, to terminate at the inner and upper part of the tibia. It is marked 8, 9, and 
is called the sartorius or tailor's muscle. It is fixed at its upper extremity, by tendinous fibres, to the anterior superior spinous 
process of the ilium, and to the curved margin of the bone beneath it: the fleshy fibres, which soon succeed to those that are 
white and tendinous, form a flat strap, about an inch or an inch and a quarter in width, which rests on the psoas and iliacus 
muscles, 17 ; on the pectineus, 18 ; and on the adductor longus, 19. Its outer side rests on the rectus femoris, 10 ; and on th^ 
vastus interims, 16. Beside the knee, it overlays the internal lateral ligament of the joint, and the tendons of the gracilis and 
semi-tend inosus muscles. Towards its lower part this muscle expands into a broad aponeurosis, which, after covering the tendons 
just named, becomes fixed to the upper and inner side of the tibia a little below its tuberosity. 

The Rectus ?nuscle. — Along the front of the thigh is stretched a muscle, which is broad and fleshy towards its middle, but 
narrow and tendinous at its extremity. It is marked 10, 11, and named the straight muscle of the thigh, (m. rectus femoris.) It 
is extended in a straight line downwards from the pelvis to the knee-pan, or patella. The middle fleshy portion, constituting the 
body of the muscle, swells out towards it central part, and tapers towards its extremities. The muscular fibres are arranged in 
two sets, one at each side ; for they pass oft' obliquely towards the edges of the muscle, somewhat as the fibrillar of a quill or 
feather do ; muscles so constructed are said to be penniform. The muscular fibres at their lower end are seen to terminate in a 
tendon, 11, the fibres of which become fixed to the upper end and anterior surface of the patella; but they do not terminate upon 
this bone : they are found to be prolonged below its lower margin, where they constitute the ligament of the patella, 13, which 
is finally fixed into the tubercle in front of the tibia. In this way the straight muscle is made to act upon the tibia, and bring it 
(if it has been previously bent) into a direct line with the thigh-bone. The upper end of the straight muscle is concealed by the 
sartorius, 8, and the tensor, 5 ; it is tendinous in its structure, and is fixed by means of two processes, of which one is attached to 
the anterior inferior spinous process of the ilium, (fig. 2, No. 2,) whilst the other is reflected outwards, and is attached to the mar- 
gin of the articular cavity of the thigh-bone. 

The Vastus Extcmus muscle. — At the outer side of the thigh is a large and long muscle, which from its length and bulk is 
called vastus externus, 15. (It is shown also in plate XXXIV. fig. 1, No. 19 ; also in fig. 2, Nos. 10, 10.) It extends from the 
greattrochanter of the thigh-bone downwards to the lower tendon of the rectus muscle, and the base of the patella, and forms 
the fleshy mass placed along the outer side of the thigh. The fibres of this muscle are observed to be attached as high up as 
the root of the great trochanter, from which point down as far as the middle of the oblique line leading to the outer condyle of the 
femur, the muscle takes points of attachment along the whole length of the linea aspera, as well as from the external surface of 
the bone. Hence the direction of the fibres varies considerably ; some of them descend straight downwards, others become 



PLATE XXXVIII. 

The deep-seated muscles of the leg are shown in these drawings. In order to expose them, the gastrocnemius, the soleus, and' the plantaris 
have been removed, and also the deep fascia which is interposed between the superficial and deep-seated muscles. 

Fig. 1. No. 1. The lower extremity of the thigh-bone-its posterior surface, where it corresponds with the popliteal space. 2. The inner 
condyle. 3. The tendinous part of the popliteus muscle. 4. The fleshy part of the same muscle. 5. The head of the fibula. 6. 
Part of the tibialis posticus muscle, corresponding with the interval between the tibia and fibula. This muscle extends higher up than 
the common flexor of the toes and the flexor of the great toe, between which it is seen at its upper part ; lower down it is overlapped by 
them and concealed. 7. The tendon of the tibialis posticus muscle, where it passes behind the inner ankle, and proceeds towards the 
sole of the foot. 8. The common flexor muscle of the toes, (m. flexor communis digitorum.) 9. Its tendon, where it passes behind 
the inner ankle, resting upon and partly concealing the tendon of the tibialis posticus. 10. The long flexor of the great toe, (m. flexor 
longus pollicis.) 1 1. Its tendon, where it passes behind the tibia to reach the sole of the foot. 12. The long peroneal muscle, (m. 
peroneus longus.) 13. Its tendon. 14. The short peroneal muscle, (m. peroneus brevis.) 15. Its tendon. 1 6. Part of the inner 
ank e. 17 The posterior surface of the os calcis. 18. The metatarsal bone of the great toe. 19, 20, 21, 22. The metatarsal bones 
of the small toes. 23, 23, 23 23. The four tendons derived from the long flexor muscle proceeding to the small toes. 24. The tendon 
of the long flexor muscle of the great toe. 25. The tendon of the peroneus longus muscle, where it turns into the sole of the foot. 
Fig. 2. No. 1. The postenor surface of the head of the tibia. 2. The head of the fibula. 3. The tibialis posticus muscle: its fibres are 
seen ans.ng from the tibia and fibu a, and passing obliquely to be fixed into the tendon which lies along its posterior aspect. 4. The 
tendon of the tibialis posticus muscle passing behind the inner ankle. 5. Part of the inner ankle. 6. Part of the external ankle. 7. 
The posterior surface of the os calcis 8, 9 10, 11, 12. The metatarsal bones of the toes. 13. The fleshy part of thelong peroneal 
muscle, m. peroneus longus.) 1-1. Its tendon passing